Method and apparatus for indicating channel in wireless local area network

ABSTRACT

The present invention discloses a method and an apparatus for indicating a channel in a wireless local area network WLAN. A sending station generates and sends a physical protocol data unit PPDU, the PPDU includes a preamble field and a data field, a high efficiency signal field HE-SIG-A of the preamble field includes a bandwidth identifier and a channel bonding identifier, and the channel bonding identifier is used to indicate whether a data transmission channel is continuous in a frequency domain. In the foregoing manner, a discontinuous channel in a frequency domain in a wireless local area network is indicated, an available channel for data transmission is improved, and a system throughput is increased.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/CN2016/111325, filed on Dec. 21, 2016, which claims priority toChinese Patent Application No. 201610084191.3, filed on Feb. 6, 2016,Chinese Patent Application No. 201610128055.X, filed on Mar. 7, 2016,and Chinese Patent Application No. 201610353330.8, filed on May 24,2016. All of which are hereby incorporated by reference in theirentireties.

TECHNICAL FIELD

The present invention relates to the field of communicationstechnologies, and in particular, to a method and an apparatus forindicating a channel in a wireless local area network.

BACKGROUND

As wireless local area network (WLAN) standards evolve, a WLAN systemobtains a higher transmission rate by using higher bandwidth. In thestandards, 20 MHz is usually used as a basic bandwidth unit. A bandwidthof 20 MHz is used in the 802.11a. The bandwidth is increased to 40 MHzin the 802.11n, and is increased to 80 MHz and 160 MHz in the 802.11ac.When the bandwidth is greater than 20 MHz, one 20 MHz channel is aprimary 20 MHz channel, and a remaining 20 MHz channel is a secondarychannel. In the current standards, when a station accesses a channel, aprimary 20 MHz channel needs to be included. That is, when the primary20 MHz channel is occupied, even if another channel is idle, the channelcannot be used. A channel bandwidth defined in the current standards hasfour modes: 20 MHz, 40 MHz, 80 MHz, and 160 (80+80) MHz.

In the next-generation WLAN standard 802.11ax, an intensive deploymentscenario is mainly studied, and a study emphasis is turned from a peakthroughput increment to spectral efficiency improvement. For a scenarioin which stations supporting different WLAN standards intensivelycoexist, for example, for a scenario in which a station supporting802.11n and a station supporting 802.11ax are intensively deployed, asshown in FIG. 1, each channel in FIG. 1 has a bandwidth of 20 MHz, an802.11n station performs transmission by using a bandwidth of 20 MHz,and a spectrum is cut during narrowband transmission performed by the802.11n station, causing channels available to an 802.11ax station to bediscontinuous.

However, existing WLAN standards are short of an indication of adiscontinuous channel in a frequency domain.

SUMMARY

In view of this, the present invention provides a method and anapparatus for indicating a channel in a wireless local area network, soas indicate a discontinuous channel in a frequency domain.

According to one aspect, the present invention provides a method forindicating a channel in a wireless local area network WLAN. The methodfor indicating a channel is applied to a downlink between an accesspoint and a station. The method for indicating a channel is performed bythe access point, and is applied to a downlink multiuser transmissionscenario between the access point and multiple stations. In the methodfor indicating a channel, a physical protocol data unit PPDU is firstgenerated. The PPDU includes a preamble field and a data field, a highefficiency signal field HE-SIG-A of the preamble field includes abandwidth identifier and a channel bonding identifier, and the channelbonding identifier is used to indicate whether a data transmissionchannel is continuous in a frequency domain. Then, the PPDU is sent.

Specifically, if the channel bonding identifier is a first value, thedata transmission channel is continuous in the frequency domain; or ifthe channel bonding identifier is a second value, the data transmissionchannel includes multiple discontinuous channels in the frequencydomain.

In a possible implementation, if the channel bonding identifier is thefirst value, and the bandwidth identifier is a first value, the datatransmission channel includes a primary 20 MHz channel; if the channelbonding identifier is the first value, and the bandwidth identifier is asecond value, the data transmission channel includes a primary 20 MHzchannel and a secondary 20 MHz channel; if the channel bondingidentifier is the first value, and the bandwidth identifier is a thirdvalue, the data transmission channel includes a primary 20 MHz channel,a secondary 20 MHz channel, and a secondary 40 MHz channel; if thechannel bonding identifier is the first value, and the bandwidthidentifier is a fourth value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel; if the channel bondingidentifier is the second value, and the bandwidth identifier is a firstvalue, the data transmission channel includes primary 20 MHz and asecondary 40 MHz channel; if the channel bonding identifier is thesecond value, and the bandwidth identifier is a second value, the datatransmission channel includes a primary 20 MHz channel and a secondary80 MHz channel; if the channel bonding identifier is the second value,and the bandwidth identifier is a third value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel,and a secondary 80 MHz channel; or if the channel bonding identifier isthe second value, and the bandwidth identifier is a fourth value, thedata transmission channel includes a primary 20 MHz channel, a secondary40 MHz channel, and a secondary 80 MHz channel.

In a possible implementation, if the bandwidth identifier is a firstvalue, the data transmission channel includes a primary 20 MHz channel;if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel; if the bandwidth identifier is a third value, and the channelbonding identifier is the first value, the data transmission channelincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel; if the bandwidth identifier is a third value,and the channel bonding identifier is the second value, the datatransmission channel includes a primary 20 MHz channel and a secondary40 MHz channel; if the bandwidth identifier is a fourth value, and thechannel bonding identifier is the first value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel; or if thebandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80MHz channel.

In a possible implementation, if the bandwidth identifier is a firstvalue, the data transmission channel includes a primary 20 MHz channel;if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel; if the bandwidth identifier is a third value, and the channelbonding identifier is the first value, the data transmission channelincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel; if the bandwidth identifier is a third value,and the channel bonding identifier is the second value, the datatransmission channel includes a primary 20 MHz channel and a secondary40 MHz channel; if the bandwidth identifier is a fourth value, and thechannel bonding identifier is the first value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel; or if thebandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 80 MHz channel.

In a possible implementation, if the bandwidth identifier is a firstvalue, the data transmission channel includes a primary 20 MHz channel;if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel; if the bandwidth identifier is a third value, and the channelbonding identifier is the first value, the data transmission channelincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel; if the bandwidth identifier is a third value,and the channel bonding identifier is the second value, the datatransmission channel includes a primary 20 MHz channel and a secondary40 MHz channel; if the bandwidth identifier is a fourth value, and thechannel bonding identifier is the first value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel; or if thebandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 80MHz channel.

In a possible implementation, if the bandwidth identifier is a firstvalue, the data transmission channel includes a primary 20 MHz channel;if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel; if the bandwidth identifier is a third value, and the channelbonding identifier is the first value, the data transmission channelincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel; if the bandwidth identifier is a third value,and the channel bonding identifier is the second value, the datatransmission channel includes a primary 20 MHz channel and a secondary40 MHz channel; or if the bandwidth identifier is a fourth value, thedata transmission channel includes a primary 20 MHz channel, a secondary20 MHz channel, a secondary 40 MHz channel, and a secondary 80 MHzchannel.

According to another aspect, the present invention provides an apparatusfor indicating a channel in a wireless local area network WLAN. Theapparatus for indicating a channel is an access point, and is applied toa downlink multiuser transmission scenario between the access point andmultiple stations. The apparatus for indicating a channel includes abaseband circuit and a radio frequency circuit. The baseband circuit isconfigured to generate a physical protocol data unit PPDU. The PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier anda channel bonding identifier, and the channel bonding identifier is usedto indicate whether a data transmission channel is continuous in afrequency domain. The radio frequency circuit is configured to send thePPDU.

Specifically, if the channel bonding identifier is a first value, thedata transmission channel is continuous in the frequency domain; or ifthe channel bonding identifier is a second value, the data transmissionchannel includes multiple discontinuous channels in the frequencydomain.

In a possible implementation, if the channel bonding identifier is thefirst value, and the bandwidth identifier is a first value, the datatransmission channel includes a primary 20 MHz channel; if the channelbonding identifier is the first value, and the bandwidth identifier is asecond value, the data transmission channel includes a primary 20 MHzchannel and a secondary 20 MHz channel; if the channel bondingidentifier is the first value, and the bandwidth identifier is a thirdvalue, the data transmission channel includes a primary 20 MHz channel,a secondary 20 MHz channel, and a secondary 40 MHz channel; if thechannel bonding identifier is the first value, and the bandwidthidentifier is a fourth value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel; if the channel bondingidentifier is the second value, and the bandwidth identifier is a firstvalue, the data transmission channel includes primary 20 MHz and asecondary 40 MHz channel; if the channel bonding identifier is thesecond value, and the bandwidth identifier is a second value, the datatransmission channel includes a primary 20 MHz channel and a secondary80 MHz channel; if the channel bonding identifier is the second value,and the bandwidth identifier is a third value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel,and a secondary 80 MHz channel; or if the channel bonding identifier isthe second value, and the bandwidth identifier is a fourth value, thedata transmission channel includes a primary 20 MHz channel, a secondary40 MHz channel, and a secondary 80 MHz channel.

In a possible implementation, if the bandwidth identifier is a firstvalue, the data transmission channel includes a primary 20 MHz channel;if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel; if the bandwidth identifier is a third value, and the channelbonding identifier is the first value, the data transmission channelincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel; if the bandwidth identifier is a third value,and the channel bonding identifier is the second value, the datatransmission channel includes a primary 20 MHz channel and a secondary40 MHz channel; if the bandwidth identifier is a fourth value, and thechannel bonding identifier is the first value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel; or if thebandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80MHz channel.

In a possible implementation, if the bandwidth identifier is a firstvalue, the data transmission channel includes a primary 20 MHz channel;if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel; if the bandwidth identifier is a third value, and the channelbonding identifier is the first value, the data transmission channelincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel; if the bandwidth identifier is a third value,and the channel bonding identifier is the second value, the datatransmission channel includes a primary 20 MHz channel and a secondary40 MHz channel; if the bandwidth identifier is a fourth value, and thechannel bonding identifier is the first value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel; or if thebandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 80 MHz channel.

In a possible implementation, if the bandwidth identifier is a firstvalue, the data transmission channel includes a primary 20 MHz channel;if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel; if the bandwidth identifier is a third value, and the channelbonding identifier is the first value, the data transmission channelincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel; if the bandwidth identifier is a third value,and the channel bonding identifier is the second value, the datatransmission channel includes a primary 20 MHz channel and a secondary40 MHz channel; if the bandwidth identifier is a fourth value, and thechannel bonding identifier is the first value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel; or if thebandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 80MHz channel.

In a possible implementation, if the bandwidth identifier is a firstvalue, the data transmission channel includes a primary 20 MHz channel;if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel; if the bandwidth identifier is a third value, and the channelbonding identifier is the first value, the data transmission channelincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel; if the bandwidth identifier is a third value,and the channel bonding identifier is the second value, the datatransmission channel includes a primary 20 MHz channel and a secondary40 MHz channel; or if the bandwidth identifier is a fourth value, thedata transmission channel includes a primary 20 MHz channel, a secondary20 MHz channel, a secondary 40 MHz channel, and a secondary 80 MHzchannel.

It can be learned from the foregoing solutions that, embodiments of thepresent invention provide a method and an apparatus for indicating achannel in a wireless local area network WLAN. A sending stationgenerates and sends a physical protocol data unit PPDU, the PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier anda channel bonding identifier, and the channel bonding identifier is usedto indicate whether a data transmission channel is continuous in afrequency domain. In the foregoing manner, a discontinuous channel in afrequency domain in a wireless local area network is indicated, anavailable data transmission channel is improved, and a system throughputis increased.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a channel allocation diagram in which an 802.11n station andan 802.11ax station coexist;

FIG. 2 is an application scenario diagram of a system according to thepresent invention;

FIG. 3a is a channel allocation diagram of a system according to thepresent invention;

FIG. 3b is another channel allocation diagram of a system according tothe present invention;

FIG. 4 is a diagram of a frame structure of a physical protocol dataunit of a system according to the present invention;

FIG. 5 is diagram of a frame structure of an HE-SIG-B of a physicalprotocol data unit of a system according to the present invention;

FIG. 6 is a diagram of allocating a resource unit of an HE-SIG-B of aphysical protocol data unit in a bandwidth of 20 MHz;

FIG. 7 is a diagram of allocating a resource unit of an HE-SIG-B of aphysical protocol data unit in a bandwidth of 40 MHz;

FIG. 8 is a diagram of allocating a resource unit of an HE-SIG-B of aphysical protocol data unit in a bandwidth of 80 MHz;

FIG. 9 is a diagram of allocating a resource unit of an HE-SIG-B of aphysical protocol data unit in a bandwidth of 160 MHz;

FIG. 10 is a flowchart of a method according to Embodiment 1 of thepresent invention;

FIG. 11 is a channel indication diagram of an implementation 1 accordingto Embodiment 1 of the present invention;

FIG. 12 is a channel indication diagram of an implementation 2 accordingto Embodiment 1 of the present invention;

FIG. 13 is a channel indication diagram of an implementation 3 accordingto Embodiment 1 of the present invention;

FIG. 14 is a channel indication diagram of an implementation 4 accordingto Embodiment 1 of the present invention;

FIG. 15 is a channel indication diagram of an implementation 5 accordingto Embodiment 1 of the present invention;

FIG. 16 is a channel indication diagram of an implementation 6 accordingto Embodiment 1 of the present invention;

FIG. 17a is a first channel indication diagram of an implementation 7according to Embodiment 1 of the present invention;

FIG. 17b is a second channel indication diagram of an implementation 7according to Embodiment 1 of the present invention;

FIG. 18a is a first channel indication diagram of an implementation 8according to Embodiment 1 of the present invention;

FIG. 18b is a second channel indication diagram of an implementation 8according to Embodiment 1 of the present invention;

FIG. 18c is a third channel indication diagram of an implementation 8according to Embodiment 1 of the present invention;

FIG. 18d is a fourth channel indication diagram of an implementation 8according to Embodiment 1 of the present invention;

FIG. 19 is a channel indication diagram of an implementation 9 accordingto Embodiment 1 of the present invention;

FIG. 20a is a first channel indication diagram of an implementation 10according to Embodiment 1 of the present invention;

FIG. 20b is a second channel indication diagram of an implementation 10according to Embodiment 1 of the present invention;

FIG. 20c is a third channel indication diagram of an implementation 10according to Embodiment 1 of the present invention;

FIG. 20d is a fourth channel indication diagram of an implementation 10according to Embodiment 1 of the present invention;

FIG. 21 is a flowchart of a method according to Embodiment 2 of thepresent invention;

FIG. 22 is a channel indication diagram according to Embodiment 2 of thepresent invention;

FIG. 23 is a channel indication diagram according to Embodiment 3 of thepresent invention;

FIG. 24 is a diagram of an apparatus according to Embodiment 4 of thepresent invention;

FIG. 25 is a channel indication diagram according to Embodiment 7 of thepresent invention;

FIG. 26 is a channel indication diagram 1 according to Embodiment 8 ofthe present invention; and

FIG. 27 is a channel indication diagram 2 according to Embodiment 8 ofthe present invention.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention may be applied to a Wireless LocalArea Network (WLAN). The wireless local area network may includemultiple basic service sets (BSS). A network node in a basic service setis a station (STA), and the station includes an access point (AP)station and a non-access point station (Non-AP STA). Each basic serviceset may include one AP and multiple non-AP STAs associated with the AP.

The access point (AP) station is also referred to as a wireless accesspoint, a hotspot, or the like. An AP is an access point at which amobile user accesses a wired network, and is mainly deployed at home andinside a building and a campus. A typical coverage radius is tens of orhundreds of meters. Certainly, the AP may be deployed outdoors. The APis equivalent to a bridge connecting a wired network and a wirelessnetwork, and is mainly configured to: connect various wireless networkclients together, and then connect the wireless network to the Ethernet.Currently, standards mainly used by the AP are the Institute ofElectrical and Electronics Engineers (IEEE), 802.11 series.Specifically, the AP may be a terminal device or a network device havinga Wireless Fidelity (Wi-Fi) chip. Optionally, the AP may be a devicesupporting the 802.11ax standard.

The non-access point (Non-AP STA) station may be a wirelesscommunications chip, a wireless sensor, or a wireless communicationsterminal, such as a mobile phone supporting a Wi-Fi communicationsfunction, a tablet computer supporting a Wi-Fi communications function,a set-top box supporting a Wi-Fi communications function, a smarttelevision supporting a Wi-Fi communications function, a smart wearabledevice supporting a Wi-Fi communications function, or a computersupporting a Wi-Fi communications function. Optionally, the station maysupport the 802.11ax standard.

FIG. 2 is a schematic diagram of a system of a typical WLAN deploymentscenario. The system includes one AP and three STAs. The AP separatelycommunicates with a STA 1, a STA 2, and a STA 3. Each of the AP and theSTAs 1 to 3 may be used as a first station or a second station.

It should be noted that, channel division in the WLAN is shown in FIG.3a , channels are numbered, and each of numbers 0 to 7 represents one 20MHz channel. The number 0 channel represents a primary 20 MHz channel.The number 1 channel represents a secondary 20 MHz channel. The number 0channel and the number 1 channel form a primary 40 MHz channel. Thenumber 2 channel and the number 3 channel form a secondary 40 MHzchannel. The number 0 channel, the number 1 channel, the number 2channel, and the number 3 channel form a primary 80 MHz channel. Thenumber 4 channel, the number 5 channel, the number 6 channel, and thenumber 7 channel form a secondary 80 MHz channel. The number 4 channelis adjacent to the number 5 channel. The number 5 channel is adjacent tothe number 6 channel. The number 6 channel is adjacent to the number 7channel.

It should be understood that, in current WLAN standards, in amultichannel composition rule, one unique 20 MHz channel is a primary 20MHz channel, and adjacent 20 MHz channel on the left or right of theprimary 20 MHz channel is a secondary 20 MHz channel (The left or theright 20 MHz channel may be randomly selected, but only one can beselected. In addition, being left may also be described as being below,and being right may also be described as being above. Being left orbelow indicates that a frequency is lower than a frequency of theprimary 20 MHz channel, and being right or above indicates that afrequency is higher than the frequency of the primary 20 MHz channel).The primary 20 MHz channel and the secondary 20 MHz channel form aprimary 40 MHz channel. Adjacent 40 MHz channel on the left or right ofthe primary 40 MHz channel is a secondary 40 MHz channel (the left orthe right 40 MHz may be randomly selected, but only one can beselected), and the primary 40 MHz channel and the secondary 40 MHzchannel form a primary 80 MHz channel. 80 MHz channel on the left orright of the primary 80 MHz channel is a secondary 80 MHz channel (theleft or the right 80 MHz channel may be randomly selected, but only onecan be selected). When the primary 80 MHz channel is adjacent to thesecondary 80 MHz channel, the primary 80 MHz channel and the secondary80 MHz channel form a 160 MHz channel. When the primary 80 MHz channelis not adjacent to the secondary 80 MHz channel, the primary 80 MHzchannel and the secondary 80 MHz channel form an (80+80) MHz channel.

Based on the foregoing rule, the channels 0 to 7 may be arranged inmultiple manners shown in FIG. 3b . In addition, two 20 MHz channels ofsecondary 40 MHz and four 20 MHz channels of secondary 80 MHz may benumbered from left to right or from right to left. This is not limitedin the present invention. For convenience of description, in allembodiments of the present invention, for the channel division in theWLAN, the number 0 channel is used as a primary 20 MHz channel.

It should be noted that, a data frame in the embodiments of the presentinvention is a possible 802.11ax data frame, and a data frame in theWLAN is generally a Physical Protocol Data Unit (PPDU). As shown in FIG.4, the PPDU includes a preamble field and a data field, and the preamblefield includes a legacy preamble field and a high efficiency preamblefield. The Legacy Preamble (L-P) field keeps compatible with an existingWLAN standard device, and includes an Legacy Short Training Field L-STF,an Legacy Long Training Field (L-LTF), an Legacy Signaling Field,(L-SIG), and an Repeated Legacy Signaling Field (RL-SIG). The legacypreamble field is followed by a high efficiency signal field A(HE-SIG-A), a high efficiency signal field B (HE-SIG-B), and an other HEpreamble. It should be noted that other HE preamble is one field or acombination of multiple fields, and is not particularly limited to aspecific field. The other HE preamble field is followed by the datafield (Data). In a further possible WLAN standard, a name of thestandard, a name of a field, or the like may be replaced with any othername, and shall not be construed as a limitation to the protection scopeof the present invention. Moreover, descriptions of the data frame arealso applicable to subsequent embodiments.

It should be noted that the HE-SIG-B field is separately encoded on each20 MHz channel. An encoding structure is shown in FIG. 5, and includes acommon block field and a user specific field.

The common block field includes information related to resourceallocation, such as frequency domain RU allocation information, an RUallocated to MU-MIMO, and a quantity of users included in the MU-MIMO.The user specific field includes multiple user block fields. Each userblock field includes information that is needed to analyze data of twostations. If a quantity of user fields indicated by RU allocationsignaling of the common block field is an odd number, the last userblock field may include information about only one station.

For a PPDU of 20 MHz, refer to FIG. 6. For a PPDU of 40 MHz, as shown inFIG. 7, a common block field and a user specific field of a station aretransmitted on 20 MHz having the same station data.

For a PPDU of 80 MHz, a frequency mapping of a common block field and auser specific field is shown in FIG. 8. Content of an HE-SIG-B on thefirst 20 MHz channel and the third 20 MHz channel that are arranged fromtop to bottom according to frequencies is the same. Information carriedon these channels is an HE-SIG-B 1, and the HE-SIG-B 1 includessignaling information of all stations whose data occupies at least somesubcarriers of A242 or C242. Similarly, content of an HE-SIG-B on thesecond 20 MHz channel and the fourth 20 MHz channel that are arrangedfrom top to bottom according to frequencies is the same. Informationcarried on these channels is an HE-SIG-B 2, and the HE-SIG-B 2 includessignaling information of all stations whose data occupies at least somesubcarriers of B242 or D242.

For a PPDU of 160 MHz, a frequency mapping of a common block field and auser specific field is shown in FIG. 9. Content of an HE-SIG-B on thefirst 20 MHz channel, the third 20 MHz channel, the fifth 20 MHzchannel, and the seventh 20 MHz channel that are arranged from top tobottom according to frequencies is the same. Information carried onthese channels is an HE-SIG-B 1, and the HE-SIG-B 1 includes signalinginformation of all stations whose data occupies at least somesubcarriers of A1-242, C1-242, A2-242, or C2-242. Similarly, content ofan HE-SIG-B on the second 20 MHz channel, the fourth 20 MHz channel, thesixth 20 MHz channel, and the eighth 20 MHz channel that are arrangedfrom top to bottom according to frequencies is the same. Informationcarried on these channels is an HE-SIG-B 2, and the HE-SIG-B 2 includessignaling information of all stations whose data occupies at least somesubcarriers of B1-242, D1-242, B2-242, or D2-242.

For convenience of description, the descriptions of the PPDU are alsoapplicable to all the embodiments.

Embodiment 1

Embodiment 1 of the present invention provides a method, which isapplied to a WLAN, for indicating a channel. The method may be appliedto a station, for example, the AP and the STA 1 to the STA 3 in FIG. 2.The station may support a next-generation WLAN standard, for example,the 802.11ax standard. FIG. 10 is an example block diagram of the methodfor indicating a channel. Specific steps are as follows:

Step 101: Generate a physical protocol data unit PPDU, where the PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier anda channel bonding identifier, and the channel bonding identifier is usedto indicate whether a data transmission channel is continuous in afrequency domain.

Step 102: Send the PPDU.

Specifically, the channel bonding (CB) identifier includes at least onebit, and one bit is used as an example below for description. If thechannel bonding identifier is a first value, the data transmissionchannel is continuous in the frequency domain; or if the channel bondingidentifier is a second value, the data transmission channel includesmultiple discontinuous channels in the frequency domain.

It should be noted that the first value and the second value of thechannel bonding identifier are not limited in the present invention. Thefirst value is “0” and the second value is “1”. The first value is “1”and the second value is “0”. The foregoing two cases are both in theprotection scope of the present invention. For convenience ofdescription, the case in which the first value is “0” and the secondvalue is “1” is specifically used below for description.

Optionally, in the present invention, indicating the data transmissionchannel by using both the bandwidth identifier and the channel bondingidentifier includes at least 10 implementations.

Implementation 1: If the channel bonding identifier is the first value,and the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the channel bonding identifier is the first value, and the bandwidthidentifier is a second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 20 MHz channel;

if the channel bonding identifier is the first value, and the bandwidthidentifier is a third value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the channel bonding identifier is the first value, and the bandwidthidentifier is a fourth value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel;

if the channel bonding identifier is the second value, and the bandwidthidentifier is a first value, the data transmission channel includesprimary 20 MHz and a secondary 40 MHz channel;

if the channel bonding identifier is the second value, and the bandwidthidentifier is a second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 80 MHz channel;

if the channel bonding identifier is the second value, and the bandwidthidentifier is a third value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 80MHz channel; or

if the channel bonding identifier is the second value, and the bandwidthidentifier is a fourth value, the data transmission channel includes aprimary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80MHz channel.

It should be noted that the bandwidth (BW) identifier includes at leasttwo bits, and two bits are used as an example below for description.Further, a value range of the first value, the second value, the thirdvalue, and the fourth value of the bandwidth identifier is [00, 01, 10,11]. A specific mapping relationship of a value of the bandwidthidentifier is not limited in the present invention. For convenience ofdescription, descriptions are provided below with reference to a case inwhich the first value is “00”, the second value is “01”, the third valueis “10”, and the fourth value is “11”.

Specifically, the implementation 1 is specifically described withreference to FIG. 11.

For a continuous channel in the frequency domain:

When CB=0 and BW=00, a data transmission bandwidth channel is a primary20 MHz channel, that is, a channel 0.

When CB=0 and BW=01, the data transmission channel includes a primary 20MHz channel and a secondary 20 MHz channel, that is, channels 0 and 1.

When CB=0 and BW=10, the data transmission channel includes a primary 20MHz channel, a secondary 20 MHz channel, and a secondary 40 MHz channel,that is, channels 0 to 3.

When CB=0 and BW=11, the data transmission channel includes a primary 20MHz channel, a secondary 20 MHz channel, and a secondary 40 MHz channel,that is, channels 0 to 7.

For discontinuous channels in the frequency domain:

When CB=1 and BW=00, the data transmission channel includes primary 20MHz and a secondary 40 MHz channel, that is, the channels 0, 2, and 3.

When CB=1 and BW=01, the data transmission channel includes a primary 20MHz channel and a secondary 80 MHz channel, that is, the channels 0 and4 to 7.

When CB=1 and BW=10, the data transmission channel includes a primary 20MHz channel, a secondary 20 MHz channel, and a secondary 80 MHz channel,that is, the channels 0, 1, and 4 to 7.

When CB=1 and BW=11, the data transmission channel includes a primary 20MHz channel, a secondary 40 MHz channel, and a secondary 80 MHz channel,that is, the channels 0 and 2 to 7.

Implementation 2:

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 40 MHz channel;

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the first value, the data transmission channel is 160 MHzor (80+80) MHz, and in this case, the data transmission channel includesa primary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel; or

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel is 160 MHzor (80+80) MHz, and in this case, the data transmission channel includesa primary 20 MHz channel, a secondary 20 MHz channel, and a secondary 80MHz channel.

With reference to FIG. 12, a mapping relationship between the channelbonding identifier and the bandwidth identifier, and the channel in theimplementation 2 is described.

When BW=00, a data transmission bandwidth is a primary 20 MHz channel,that is, the channel 0. A value of the channel bonding identifier may be0, 1, or reserved.

When BW=01, the data transmission bandwidth is a primary 20 MHz channeland a secondary 20 MHz channel, that is, the channels 0 and 1. The valueof the channel bonding identifier may be 0, 1, or reserved.

When BW=10 and CB=0, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 20 MHz channel, and a secondary 40 MHz channel,that is, the channels 0 to 3.

When BW=10 and CB=1, the data transmission bandwidth is a primary 20 MHzchannel and a secondary 40 MHz channel, that is, the channels 0, 2, and3.

When BW=11 and CB=0, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel, that is, the channels 0 to 7.

When BW=11 and CB=1, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 20 MHz channel, and a secondary 80 MHz channel,that is, the channels 0, 1, and 4 to 7.

Implementation 3:

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 40 MHz channel;

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the first value, the data transmission channel is 160 MHzor (80+80) MHz, and in this case, the data transmission channel includesa primary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel; or

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel is 160 MHzor (80+80) MHz, and in this case, the data transmission channel includesa primary 20 MHz channel and a secondary 80 MHz channel.

With reference to FIG. 13, a mapping relationship between the channelbonding identifier and the bandwidth identifier, and the channel inimplementation 3 is described.

When BW=00, a data transmission bandwidth is a primary 20 MHz channel,that is, the channel 0. When the data transmission bandwidth is lessthan or equal to 40 MHz, a value of the channel bonding identifier maybe 0, 1, or reserved.

When BW=01, the data transmission bandwidth is a primary 20 MHz channeland a secondary 20 MHz channel, that is, the channels 0 and 1. When thedata transmission bandwidth is less than or equal to 40 MHz, the valueof the channel bonding identifier may be 0, 1, or reserved.

When BW=10 and CB=0, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 20 MHz channel, and a secondary 40 MHz channel,that is, the channels 0 to 3.

When BW=10 and CB=1, the data transmission bandwidth is a primary 20 MHzchannel and a secondary 40 MHz channel, that is, the channels 0, 2, and3.

When BW=11 and CB=0, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel, that is, the channels 0 to 7.

When BW=11 and CB=1, the data transmission bandwidth is a primary 20 MHzchannel and a secondary 80 MHz channel, that is, the channels 0 and 4 to7.

Implementation 4:

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 40 MHz channel;

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the first value, the data transmission channel is 160 MHzor (80+80) MHz, and in this case, the data transmission channel includesa primary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel; or

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel is 160 MHzor (80+80) MHz, and in this case, the data transmission channel includesa primary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80MHz channel.

With reference to FIG. 14, a mapping relationship between the channelbonding identifier and the bandwidth identifier, and the channel inmanner 4 is described.

When BW=00, a data transmission bandwidth is a primary 20 MHz channel,that is, the channel 0. A value of the channel bonding identifier may be0, 1, or reserved.

When BW=01, the data transmission bandwidth is a primary 20 MHz channeland a secondary 20 MHz channel, that is, the channels 0 and 1. The valueof the channel bonding identifier may be 0, 1, or reserved.

When BW=10 and CB=0, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 20 MHz channel, and a secondary 40 MHz channel,that is, the channels 0 to 3.

When BW=10 and CB=1, the data transmission bandwidth is a primary 20 MHzchannel and a secondary 40 MHz channel, that is, the channels 0, 2, and3.

When BW=11 and CB=0, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel, that is, the channels 0 to 7.

When BW=11 and CB=1, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 40 MHz channel, and a secondary 80 MHz channel,that is, the channels 0 and 2 to 7.

Implementation 5:

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 40 MHz channel; or

if the bandwidth identifier is a fourth value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel.

With reference to FIG. 15, a mapping relationship between the channelbonding identifier and the bandwidth identifier, and the channel inmanner 5 is described.

When BW=00, a data transmission bandwidth is a primary 20 MHz channel,that is, the channel 0. A value of the channel bonding identifier may be0, 1, or reserved.

When BW=01, the data transmission bandwidth is a primary 20 MHz channeland a secondary 20 MHz channel, that is, the channels 0 and 1. The valueof the channel bonding identifier may be 0, 1, or reserved.

When BW=10 and CB=0, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 20 MHz channel, and a secondary 40 MHz channel,that is, the channels 0 to 3.

When BW=10 and CB=1, the data transmission bandwidth is a primary 20 MHzchannel and a secondary 40 MHz channel, that is, the channels 0, 2, and3.

When BW=11, the data transmission bandwidth is a primary 20 MHz channel,a secondary 20 MHz channel, a secondary 40 MHz channel, and a secondary80 MHz channel, that is, the channels 0 to 7. The value of the channelbonding identifier may be 0, 1, or reserved.

Implementation 6:

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel,and a secondary 40 MHz channel;

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel; or

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 80MHz channel.

With reference to FIG. 16, a mapping relationship between the channelbonding identifier and the bandwidth identifier, and the channel inmanner 6 is described.

When BW=00, a data transmission bandwidth is a primary 20 MHz channel,that is, the channel 0. A value of the channel bonding identifier may be0, 1, or reserved.

When BW=01, the data transmission bandwidth is a primary 20 MHz channeland a secondary 20 MHz channel, that is, the channels 0 and 1. The valueof the channel bonding identifier may be 0, 1, or reserved.

When BW=10, the data transmission bandwidth is a primary 20 MHz channel,a secondary 20 MHz channel, and a secondary 40 MHz channel, that is, thechannels 0 to 3. The value of the channel bonding identifier may be 0,1, or reserved.

When BW=11 and CB=0, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 40 MHz channel, and a secondary 80 MHz channel,that is, the channels 0 to 7.

When BW=11 and CB=1, the data transmission bandwidth is a primary 20 MHzchannel, a secondary 20 MHz channel, and a secondary 80 MHz channel,that is, the channels 0, 1, and 4 to 7.

Implementation 7:

In the implementation 7, there are following six indicated bandwidthmodes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and a secondary 80 MHz channel; or

a primary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80MHz channel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 80 MHz channel; or

a primary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel.

For the indication manners in the six modes, indication is performed byusing both a BW field (two bits) and a CB field (one bit). {BW, CB} haseight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1}, {2,0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 1. In principle, foreach channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 1 is recommended in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 1 Mode 1 2 3 4 5 6 {BW, CB} {0, 0} {1, 0} or {2, 0} {2, 1} {3, 0}{3, 1} or {1, 1} {0, 1}

It can be learned from FIG. 17a and FIG. 17b that, for each indicationmanner, a receiving station may obtain an HE-SIG-B 1 and an HE-SIG-B 2from a fixed location (for a 20 MHz channel mode, only the HE-SIG-B 1exists and no HE-SIG-B 2 exists). Even if one indication mannercorresponds to multiple bandwidth modes, obtaining of the HE-SIG-B 1 andthe HE-SIG-B 2 is not affected. When {BW, CB}={2, 0}, either of theHE-SIG-B 1 and the HE-SIG-B 2 may be obtained by using a primary 20 MHzchannel, and the other part of an HE-SIG-B is obtained by using a 20 MHzchannel of secondary 40 MHz. When specific frequencies are arranged indescending order, when the primary 20 MHz channel is on a 20 MHz channelthat is numbered by using an odd number (shown in FIG. 17a ), the otherpart of the HE-SIG-B may be obtained by using a 20 MHz channel, which isnumbered by using an even number, of the secondary 40 MHz channel. Incontrast, when the primary 20 MHz channel is on a 20 MHz channel that isnumbered by using an even number (shown in FIG. 17b ), the other part ofthe HE-SIG-B may be obtained by using a 20 MHz channel, which isnumbered by using an odd number, of the secondary 40 MHz channel.

When {BW, CB}={2, 1}, the primary 20 MHz channel and the secondary 20MHz channel include an HE-SIG-B 1 and an HE-SIG-B 2, the secondary 40MHz channel also includes the HE-SIG-B 1 and the HE-SIG-B 2, and thereceiving station may determine by itself from which to obtain theHE-SIG-B 1 and the HE-SIG-B 2.

It should be noted that descriptions of the HE-SIG-B 1 and the HE-SIG-B2 in this implementation are also applicable to other implementations ofthe present invention.

Implementation 8:

In this embodiment, a secondary 80 MHz channel is divided into twocontinuous 40 MHz channels, and the two 40 MHz channels may beclassified according to different rules. For example, the two 40 MHzchannels are classified into an upper 40 MHz channel (a 40 MHz channelhaving a higher frequency) and a lower 40 MHz channel (a 40 MHz channelhaving a lower frequency) according to frequencies. For another example,the two 40 MHz channels are classified into a near 40 MHz channel and afar 40 MHz channel according to distances to the primary 20 MHz channel.A classification rule is not limited in this patent solution, and anindication principle thereof is similar. For convenience, an example ofthe upper 40 MHz channel and the lower 40 MHz channel is used indescriptions of subsequent embodiments for description.

In the implementation 8, there are following six bandwidth modes shownin FIG. 18 a:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and a lower 40 MHz channel of secondary80 MHz channel; or

a primary 20 MHz channel, a secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel and asecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 40MHz channel, and a secondary 80 MHz channel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel.

For the indication manners in the six modes, indication is performed byusing both a BW field (two bits) and a CB field (one bit). {BW, CB} haseight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1}, {2,0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 2. In principle, foreach channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 2 is recommended in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 2 Mode 1 2 3 4 5 6 {BW, CB} {0, 0} {1, 0} or {2, 0} {2, 1} {3, 0}{3, 1} or {1, 1} {0, 1}

FIG. 18b shows another implementation, and the implementation includesthe following six channel modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and an upper 40 MHz channel ofsecondary 80 MHz channel; or

a primary 20 MHz channel, a secondary 40 MHz channel, and an upper 40MHz channel of secondary 80 MHz channel; or a primary 20 MHz channel anda secondary 80 MHz channel; or a primary 20 MHz channel, a secondary 40MHz channel, and a secondary 80 MHz channel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel.

For the indication manners in the six modes, indication is performed byusing both a BW field (two bits) and a CB field (one bit). {BW, CB} haseight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1}, {2,0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 3. In principle, foreach channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 3 is recommended in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 3 Mode 1 2 3 4 5 6 {BW, CB} {0, 0} {1, 0} or {2, 0} {2, 1} {3, 0}{3, 1} or {1, 1} {0, 1}

FIG. 18c shows another implementation, and the implementation includesthe following seven channel modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and a lower 40 MHz channel of secondary80 MHz channel; or

a primary 20 MHz channel, a secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel and asecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 40MHz channel, and a secondary 80 MHz channel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel.

Mode 7: a primary 20 MHz channel and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 40MHz channel, and an upper 40 MHz channel of secondary 80 MHz channel; ora primary 20 MHz channel and a secondary 80 MHz channel; or a primary 20MHz channel, a secondary 40 MHz channel, and a secondary 80 MHz channel.

For the indication manners in the seven modes, indication is performedby using both a BW field (two bits) and a CB field (one bit). {BW, CB}has eight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1},{2, 0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 4. In principle,for each channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 4 is described in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 4 Mode 1 2 3 4 5 6 7 {BW, {0, 0} {1, 0} {2, 0} {2, 1} {3, 0} {3,1} {0, 1} CB} or {1, 1}

FIG. 18d shows another implementation, and the implementation includesthe following eight channel modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and a lower 40 MHz channel of secondary80 MHz channel; or

a primary 20 MHz channel, a secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel and asecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 40MHz channel, and a secondary 80 MHz channel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel.

Mode 7: a primary 20 MHz channel and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 40MHz channel, and an upper 40 MHz channel of secondary 80 MHz channel; ora primary 20 MHz channel and a secondary 80 MHz channel; or a primary 20MHz channel, a secondary 40 MHz channel, and a secondary 80 MHz channel.

Mode 8: a primary 20 MHz channel, a secondary 40 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 40MHz channel, and a secondary 80 MHz channel.

For the indication manners in the eight modes, indication is performedby using both a BW field (two bits) and a CB field (one bit). {BW, CB}has eight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1},{2, 0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 5. In principle,for each channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 5 is described in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 5 Mode 1 2 3 4 5 6 7 8 {BW, CB} {0, 0} {1, 1} {2, 0} {2, 1} {3, 0}{3, 1} {0, 1} {1, 0}

Implementation 9:

In this embodiment, a secondary 40 MHz channel is divided into two 20MHz channels. The two 20 MHz channels may be classified according todifferent rules. For example, the two 20 MHz channels are classifiedinto an upper 20 MHz channel (a 20 MHz channel having a higherfrequency) and a lower 20 MHz channel (a 20 MHz channel having a lowerfrequency) according to frequencies. For another example, the two 20 MHzchannels are classified into a near 20 MHz channel and a far 20 MHzchannel according to distances to the primary 20 MHz channel. Aclassification rule is not limited in this patent solution, and anindication principle thereof is similar. For convenience, an example ofthe upper 20 MHz channel and the lower 20 MHz channel is used indescriptions of subsequent embodiments for description. In theimplementation 9, there are following six bandwidth modes shown in FIG.19:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel; or aprimary 20 MHz channel and a 20 MHz channel of a secondary 40 MHzchannel.

Specifically, when the primary 20 MHz channel is on a channel, which isnumbered by using an odd number, in descending order of frequencies, the20 MHz channel is a 20 MHz channel, which is numbered by using an evennumber, of the secondary 40 MHz channel. When the primary 20 MHz channelis on a channel, which is numbered by using an even number, indescending order of frequencies, the 20 MHz channel is a 20 MHz channel,which is numbered by using an odd number, of the secondary 40 MHzchannel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 20 MHz channel of secondary 40 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, and an upper 20 MHz channel ofsecondary 40 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and a secondary 80 MHz channel; or aprimary 20 MHz channel, a lower 20 MHz channel of secondary 40 MHzchannel, and a secondary 80 MHz channel; or a primary 20 MHz channel, anupper 20 MHz channel of secondary 40 MHz channel, and a secondary 80 MHzchannel; or a primary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, a lower 20 MHz channel of secondary 40 MHz channel, and asecondary 80 MHz; or a primary 20 MHz channel, a secondary 20 MHzchannel, an upper 20 MHz channel of secondary 40 MHz channel, and asecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, a secondary 40 MHz channel, and a secondary 80 MHz channel.

For the indication manners in the six modes, indication is performed byusing both a BW field (two bits) and a CB field (one bit). {BW, CB} haseight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1}, {2,0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 6. In principle, foreach channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 6 is described in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 6 Mode 1 2 3 4 5 6 {BW, {0, 0} {1, 0} or {2, 0} {2, 1} {3, 0} {3,1} auxiliary or {1, 1} indication} {0, 1}

Implementation 10:

In this embodiment, a secondary 40 MHz channel is divided into two 20MHz channels, and a secondary 80 MHz channel is divided into twocontinuous 40 MHz channels. For convenience, an example in which the two20 MHz channels and the two 40 MHz channels that are obtained afterdivision are respectively an upper 20 MHz channel, a lower 20 MHzchannel, an upper 40 MHz channel, and a lower 40 MHz channel is used indescriptions of subsequent embodiments for description.

In the implementation 10, there are following six bandwidth modes shownin FIG. 20 a:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel; or aprimary 20 MHz channel and a 20 MHz channel of a secondary 40 MHzchannel. Specifically, when the primary 20 MHz channel is on a channel,which is numbered by using an odd number, in descending order offrequencies, the 20 MHz channel is a 20 MHz channel, which is numberedby using an even number, of the secondary 40 MHz channel. When theprimary 20 MHz channel is on a channel, which is numbered by using aneven number, in descending order of frequencies, the 20 MHz channel is a20 MHz channel, which is numbered by using an odd number, of thesecondary 40 MHz channel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 20 MHz channel of secondary 40 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, and an upper 20 MHz channel ofsecondary 40 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and a lower 40 MHz channel of secondary80 MHz channel; or a primary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel and a secondary 80 MHz channel; ora primary 20 MHz channel, a secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel, anupper 20 MHz channel of secondary 40 MHz channel, and a secondary 80 MHzchannel; or a primary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 40 MHz channel, and a secondary 80 MHzchannel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel, a secondary 20 MHz channel, alower 20 MHz channel of secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel, asecondary 20 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHz channel,and a lower 40 MHz channel of secondary 80 MHz channel; or a primary 20MHz channel, a secondary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHz channel,and a secondary 80 MHz channel; or a primary 20 MHz channel, a secondary20 MHz channel, and an upper 40 MHz channel of secondary 80 MHz channel;or a primary 20 MHz channel, a secondary 20 MHz channel, an upper 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, a lower 20 MHz channel of secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel.

For the indication manners in the six modes, indication is performed byusing both a BW field (two bits) and a CB field (one bit). {BW, CB} haseight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1}, {2,0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 7. In principle, foreach channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 7 is described in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 7 Mode 1 2 3 4 5 6 {BW, {0, 0} or {1, 0} or {2, 0} {2, 1} {3, 0}{3, 1} CB} {0, 1} {1, 1}

FIG. 20b shows another implementation, and the implementation includesthe following six channel modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel; or

a primary 20 MHz channel and a 20 MHz channel of a secondary 40 MHzchannel.

Specifically, when the primary 20 MHz channel is on a channel, which isnumbered by using an odd number, in descending order of frequencies, the20 MHz channel is a 20 MHz channel, which is numbered by using an evennumber, of the secondary 40 MHz channel. When the primary 20 MHz channelis on a channel, which is numbered by using an even number, indescending order of frequencies, the 20 MHz channel is a 20 MHz channel,which is numbered by using an odd number, of the secondary 40 MHzchannel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 20 MHz channel of secondary 40 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, and an upper 20 MHz channel ofsecondary 40 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, an upper 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a lower 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel and a secondary 80MHz channel; or a primary 20 MHz channel, a secondary 40 MHz channel,and an upper 40 MHz channel of secondary 80 MHz channel; or a primary 20MHz channel, an upper 20 MHz channel of secondary 40 MHz channel, and asecondary 80 MHz channel; or a primary 20 MHz channel, a lower 20 MHzchannel of secondary 40 MHz channel, and a secondary 80 MHz channel; ora primary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80MHz channel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel, a secondary 20 MHz channel, alower 20 MHz channel of secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel, asecondary 20 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHz channel,and a lower 40 MHz channel of secondary 80 MHz channel; or a primary 20MHz channel, a secondary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHz channel,and a secondary 80 MHz channel; or a primary 20 MHz channel, a secondary20 MHz channel, and an upper 40 MHz channel of secondary 80 MHz channel;or a primary 20 MHz channel, a secondary 20 MHz channel, an upper 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, a lower 20 MHz channel of secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel.

For the indication manners in the six modes, indication is performed byusing both a BW field (two bits) and a CB field (one bit). {BW, CB} haseight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1}, {2,0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 8. In principle, foreach channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 8 is described in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 8 Mode 1 2 3 4 5 6 {BW, CB} {0, 0} {1, 0} or {2, 0} {2, 1} {3, 0}{3, 1} or {1, 1} {0, 1}

FIG. 20c shows another implementation, and the implementation includesthe following seven channel modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel; or

a primary 20 MHz channel and a 20 MHz channel of a secondary 40 MHzchannel. Specifically, when the primary 20 MHz channel is on a channel,which is numbered by using an odd number, in descending order offrequencies, the 20 MHz channel is a 20 MHz channel, which is numberedby using an even number, of the secondary 40 MHz channel. When theprimary 20 MHz channel is on a channel, which is numbered by using aneven number, in descending order of frequencies, the 20 MHz channel is a20 MHz channel, which is numbered by using an odd number, of thesecondary 40 MHz channel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 20 MHz channel of secondary 40 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, and an upper 20 MHz channel ofsecondary 40 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and a lower 40 MHz channel of secondary80 MHz channel; or a primary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel and a secondary 80 MHz channel; ora primary 20 MHz channel, a secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel, anupper 20 MHz channel of secondary 40 MHz channel, and a secondary 80 MHzchannel; or a primary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 40 MHz channel, and a secondary 80 MHzchannel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel, a secondary 20 MHz channel, alower 20 MHz channel of secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel, asecondary 20 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHz channel,and a lower 40 MHz channel of secondary 80 MHz channel; or a primary 20MHz channel, a secondary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHz channel,and a secondary 80 MHz channel; or a primary 20 MHz channel, a secondary20 MHz channel, and an upper 40 MHz channel of secondary 80 MHz channel;or a primary 20 MHz channel, a secondary 20 MHz channel, an upper 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, a lower 20 MHz channel of secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel.

Mode 7: a primary 20 MHz channel and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, an upper 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a lower 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a lower 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel.

For the indication manners in the seven modes, indication is performedby using both a BW field (two bits) and a CB field (one bit). {BW, CB}has eight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1},{2, 0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 9. In principle,for each channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 9 is described in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 9 Mode 1 2 3 4 5 6 7 {BW, {0, 0} {1, 0} {2, 0} {2, 1} {3, 0} {3,1} {0, 1} CB} or {1, 1}

FIG. 20d shows another implementation, and the implementation includesthe following eight channel modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel and a secondary 40 MHz channel; or

a primary 20 MHz channel and a 20 MHz channel of a secondary 40 MHzchannel.

Specifically, when the primary 20 MHz channel is on a channel, which isnumbered by using an odd number, in descending order of frequencies, the20 MHz channel is a 20 MHz channel, which is numbered by using an evennumber, of the secondary 40 MHz channel. When the primary 20 MHz channelis on a channel, which is numbered by using an even number, indescending order of frequencies, the 20 MHz channel is a 20 MHz channel,which is numbered by using an odd number, of the secondary 40 MHzchannel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 20 MHz channel of secondary 40 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, and an upper 20 MHz channel ofsecondary 40 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 40 MHz channel.

Mode 5: a primary 20 MHz channel and a lower 40 MHz channel of secondary80 MHz channel; or a primary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel and a secondary 80 MHz channel; ora primary 20 MHz channel, a secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel, anupper 20 MHz channel of secondary 40 MHz channel, and a secondary 80 MHzchannel; or a primary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 40 MHz channel, and a secondary 80 MHzchannel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and alower 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a lower 40 MHz channel of secondary 80 MHzchannel; or a primary 20 MHz channel, a secondary 20 MHz channel, alower 20 MHz channel of secondary 40 MHz channel, and a lower 40 MHzchannel of secondary 80 MHz channel; or a primary 20 MHz channel, asecondary 20 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHz channel,and a lower 40 MHz channel of secondary 80 MHz channel; or a primary 20MHz channel, a secondary 20 MHz channel, an upper 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a lower 20 MHz channel ofsecondary 40 MHz channel, and a secondary 80 MHz channel; or a primary20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHz channel,and a secondary 80 MHz channel; or a primary 20 MHz channel, a secondary20 MHz channel, and an upper 40 MHz channel of secondary 80 MHz channel;or a primary 20 MHz channel, a secondary 20 MHz channel, an upper 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a secondary 20MHz channel, a lower 20 MHz channel of secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel; or a primary 20 MHzchannel, a secondary 20 MHz channel, a secondary 40 MHz channel, and anupper 40 MHz channel of secondary 80 MHz channel.

Mode 7: a primary 20 MHz channel and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, an upper 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a lower 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel; or a primary 20 MHz channel, a lower 20 MHzchannel of secondary 40 MHz channel, and an upper 40 MHz channel ofsecondary 80 MHz channel.

Mode 8: a primary 20 MHz channel and a 20 MHz channel of a secondary 40MHz channel. Specifically, when the primary 20 MHz channel is on achannel, which is numbered by using an odd number, in descending orderof frequencies, the 20 MHz channel is a 20 MHz channel, which isnumbered by using an odd number, of the secondary 40 MHz channel. Whenthe primary 20 MHz channel is on a channel, which is numbered by usingan even number, in descending order of frequencies, the 20 MHz channelis a 20 MHz channel, which is numbered by using an even number, of thesecondary 40 MHz channel.

For the indication manners in the eight modes, indication is performedby using both a BW field (two bits) and a CB field (one bit). {BW, CB}has eight indication manners in total: {0, 0}, {0, 1}, {1, 0}, {1, 1},{2, 0}, {2, 1}, {3, 0}, and {3, 1}, as shown in Table 10. In principle,for each channel mode, one or more indication manners may be randomlyselected from the eight indication manners without repetition. Acorresponding manner shown in Table 10 is described in this embodiment.Another manner of corresponding between an indication manner and achannel mode is also applicable to this embodiment.

TABLE 10 Mode 1 2 3 4 5 6 7 8 {BW, CB} {0, 0} {1, 1} {2, 0} {2, 1} {3,0} {3, 1} {0, 1} {1, 0}

This embodiment of the present invention provides a method forindicating a channel in a wireless local area network WLAN. A sendingstation generates and sends a physical protocol data unit PPDU, the PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier anda channel bonding identifier, and the channel bonding identifier is usedto indicate whether a data transmission channel is continuous in afrequency domain. In the foregoing manner, a discontinuous channel in afrequency domain in a wireless local area network is indicated, anavailable data transmission channel is improved, and a system throughputis increased.

Embodiment 2

Embodiment 2 of the present invention provides a method, which isapplied to a WLAN, for indicating a channel. The method may be appliedto a station, for example, the AP and the STA 1 to the STA 3 in FIG. 2.The station may support a next-generation WLAN standard, for example,the 802.11ax standard. FIG. 21 is an example block diagram of the methodfor indicating a channel. Specific steps are as follows:

Step 201: Generate a physical protocol data unit PPDU, where the PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier anda secondary 20 MHz channel identifier, and when the bandwidth identifierindicates that a bandwidth of a data transmission channel is greaterthan 40 MHz, the secondary 20 MHz channel identifier is used to indicatewhether a secondary 20 MHz channel is available.

Step 202: Send the PPDU.

Specifically, the secondary 20 MHz channel identifier includes at leastone bit, and one bit is used as an example below for description. If thesecondary 20 MHz channel identifier is a first value, the secondary 20MHz channel is unavailable; or if the secondary 20 MHz channelidentifier is a second value, the secondary 20 MHz channel is available.

It should be noted that the first value and the second value of thesecondary 20 MHz channel identifier are not limited in the presentinvention. The first value is “0” and the second value is “1”. The firstvalue is “1” and the second value is “0”. The foregoing two cases areboth in the protection scope of the present invention. For convenienceof description, the case in which the first value is “0” and the secondvalue is “1” is specifically used below for description.

Specifically, the sending station indicates the data transmissionchannel by using the bandwidth identifier and the secondary 20 MHzchannel identifier.

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, and the secondary 20 MHzchannel identifier is the first value, the data transmission channelincludes a primary 20 MHz channel and a secondary 40 MHz channel;

if the bandwidth identifier is a third value, and the secondary 20 MHzchannel identifier is the second value, the data transmission channelincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel;

if the bandwidth identifier is a fourth value and the secondary 20 MHzchannel identifier is the first value, the data transmission channel is160 MHz or (80+80) MHz, and the data transmission channel does notinclude a secondary 20 MHz channel, that is, includes a primary 20 MHzchannel and a secondary 80 MHz channel, or includes a primary 20 MHzchannel, a secondary 40 MHz channel, and a secondary 80 MHz channel; orif the bandwidth identifier is a fourth value and the secondary 20 MHzchannel identifier is the second value, a bandwidth of the datatransmission channel is 160 MHz or (80+80) MHz, and the datatransmission channel includes a secondary 20 MHz channel, that is,includes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 80 MHz channel, or includes a primary 20 MHz channel, asecondary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80MHz channel.

It should be noted that the bandwidth identifier includes at least twobits and the secondary 20 MHz channel identifier includes at least onebit. For convenience of description, an example in which the bandwidthidentifier includes two bits and the secondary 20 MHz channel identifierincludes one bit is used for description in this embodiment.

It should be noted that definitions of the first value to the fourthvalue of the bandwidth identifier are already described in Embodiment 1,and the definitions are also applicable to subsequent implementations.

With reference to FIG. 22, a mapping relationship between the secondary20 MHz channel identifier and the bandwidth identifier, and the channelis described.

When BW=00, a data transmission bandwidth channel is a primary 20 MHzchannel, that is, a channel 0. When the data transmission bandwidth isless than or equal to 40 MHz, a value of a channel bonding identifiermay be 0, 1, or reserved.

When BW=01, the data transmission channel includes a primary 20 MHzchannel and a secondary 20 MHz channel, that is, the channel 0 and achannel 1. When the data transmission bandwidth is less than or equal to40 MHz, the value of the channel bonding identifier may be 0, 1, orreserved.

When BW=10 and the secondary 20 MHz channel identifier=0, the datatransmission channel includes a primary 20 MHz channel and a secondary40 MHz channel, that is, the channel 0, a channel 2, and a channel 3.

When BW=10 and the secondary 20 MHz channel identifier=1, the datatransmission channel includes a primary 20 MHz channel, a secondary 20MHz channel, and a secondary 40 MHz channel, that is, the channels 0 to3.

When BW=11 and the secondary 20 MHz channel identifier=0, the datatransmission channel includes a primary 20 MHz channel and a secondary80 MHz channel, that is, the channel 0 and channels 4 to 7.Alternatively, the data transmission channel includes a primary 20 MHzchannel, a secondary 40 MHz channel, and a secondary 80 MHz channel,that is, the channels 0 and 2 to 7.

When BW=11 and the secondary 20 MHz channel identifier=1, the datatransmission channel includes a primary 20 MHz channel, a secondary 20MHz channel, a secondary 40 MHz channel, and a secondary 80 MHz channel,that is, the channels 0 to 7. Alternatively, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel,and a secondary 80 MHz channel, that is, the channels 0, 1, and 4 to 7.

This embodiment of the present invention provides a method forindicating a channel in a wireless local area network WLAN. A sendingstation generates and sends a physical protocol data unit PPDU, the PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier anda secondary 20 MHz channel identifier, and when the bandwidth identifierindicates that a data transmission channel is greater than 40 MHz, thesecondary 20 MHz channel identifier is used to indicate whether asecondary 20 MHz channel is available. In the foregoing manner, adiscontinuous channel in a frequency domain in a wireless local areanetwork is indicated, an available data transmission channel isimproved, and a system throughput is increased.

Embodiment 3

Embodiment 3 of the present invention provides a method, which isapplied to a WLAN, for indicating a channel. The method may be appliedto a station, for example, the AP and the STA 1 to the STA 3 in FIG. 2.The station may support a next-generation WLAN standard, for example,the 802.11ax standard.

In this embodiment, a data transmission channel is indicated by using abandwidth identifier in a PPDU, and the bandwidth (BW) identifierincludes at least two bits.

With reference to FIG. 23, a mapping relationship between the bandwidthidentifier and the channel is described.

When BW=00, it indicates that a current data transmission channelincludes a primary 20 MHz channel.

When BW=01, it indicates that the current data transmission channelincludes a primary 20 MHz channel and a secondary 20 MHz channel.

When BW=10, it indicates that the current data transmission channelincludes a primary 20 MHz channel and a secondary 40 MHz channel; orincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel.

When BW=11, it indicates that a current data transmission channelincludes a primary 20 MHz channel and a secondary 80 MHz channel; orincludes a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 80 MHz channel; or includes a primary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel; or includes aprimary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel.

When BW=2, either of an HE-SIG-B 1 and an HE-SIG-B 2 may be obtained byusing a primary 20 MHz channel, and the other part of an HE-SIG-B isobtained by using a 20 MHz channel of secondary 40 MHz. When specificfrequencies are arranged in descending order, when the primary 20 MHzchannel is on a 20 MHz channel that is numbered by using an odd number,the other part of the HE-SIG-B may be obtained by using a 20 MHzchannel, which is numbered by using an even number, of the secondary 40MHz channel. In contrast, when the primary 20 MHz channel is on a 20 MHzchannel that is numbered by using an even number, the other part of theHE-SIG-B may be obtained by using a 20 MHz channel, which is numbered byusing an odd number, of the secondary 40 MHz channel.

When BW=3, either of an HE-SIG-B 1 and an HE-SIG-B 2 may be obtained byusing a primary 20 MHz channel, and the other part of an HE-SIG-B isobtained by using a 20 MHz channel of secondary 80 MHz. When specificfrequencies are arranged in descending order, when the primary 20 MHzchannel is on a 20 MHz channel that is numbered by using an odd number,the other part of the HE-SIG-B may be obtained by using any 20 MHzchannel, which is numbered by using an even number, of the secondary 80MHz channel. In contrast, when the primary 20 MHz channel is on a 20 MHzchannel that is numbered by using an even number, the other part of theHE-SIG-B may be obtained by using any 20 MHz channel, which is numberedby using an odd number, of the secondary 80 MHz channel.

This embodiment of the present invention provides a method forindicating a channel in a wireless local area network WLAN. A sendingstation generates and sends a physical protocol data unit PPDU, the PPDUincludes a preamble field and a data field, and a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier. Inthe foregoing manner, a discontinuous channel in a frequency domain in awireless local area network is indicated, an available data transmissionchannel is improved, and a system throughput is increased.

Embodiment 4

Referring to FIG. 24, FIG. 24 is a schematic block diagram of anapparatus for indicating a channel in a wireless local area networkaccording to Embodiment 4 of the present invention. The apparatus is,for example, an access point, or a dedicated circuit or a chipimplementing a related function. The access point 1000 includes aprocessor 1010, a memory 1020, a baseband circuit 1030, a radiofrequency circuit 1040, and an antenna 1050. The apparatus may be the APshown in FIG. 2. The AP communicates with a STA 1, a STA 2, and a STA 3.

Specifically, the processor 1010 controls operations of the access point1000. The memory 1020 may include a read-only memory and a random accessmemory, and provide instructions and data to the processor 1010. Theprocessor may be a general purpose processor, a digital signalprocessor, an application-specific integrated circuit, a fieldprogrammable gate array, or another programmable logic device. A part ofthe memory 1020 may further include a non-volatile random access memory(NVRAM). The baseband circuit 1030 is configured to generate ato-be-transmitted baseband signal, or to decode a received basebandsignal. The radio frequency circuit 1040 is configured to modulate alow-frequency baseband signal to a high-frequency carrier signal, andthe high-frequency carrier signal is transmitted by using the antenna1050. The radio frequency circuit is also configured to demodulate ahigh-frequency signal received by the antenna 1050 to a low-frequencycarrier signal. The components of the access point 1000 are coupledtogether by using a bus system 1060. In addition to a data bus, the bussystem 1060 includes a power bus, a control bus, and a status signalbus. However, for clear description, various buses in the figure aremarked as the bus system 1060. It should be noted that the foregoingdescriptions of the access point structure may be applied to subsequentembodiments.

The baseband circuit 1030 is configured to generate a physical protocoldata unit PPDU, where the PPDU includes a preamble field and a datafield, a high efficiency signal field HE-SIG-A of the preamble fieldincludes a bandwidth identifier and a channel bonding identifier, andthe channel bonding identifier is used to indicate whether a datatransmission channel is continuous in a frequency domain.

The radio frequency circuit 1040 is configured to send the PPDU.

Specifically, if the channel bonding identifier is a first value, thedata transmission channel is continuous in the frequency domain; or ifthe channel bonding identifier is a second value, the data transmissionchannel includes multiple discontinuous channels in the frequencydomain.

Optionally, the apparatus for indicating a channel indicates the datatransmission channel by using both the bandwidth identifier and thechannel bonding identifier, and indication manners are specifically asfollows:

Manner 1:

If the channel bonding identifier is the first value, and the bandwidthidentifier is a first value, the data transmission channel includes aprimary 20 MHz channel;

if the channel bonding identifier is the first value, and the bandwidthidentifier is a second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 20 MHz channel;

if the channel bonding identifier is the first value, and the bandwidthidentifier is a third value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the channel bonding identifier is the first value, and the bandwidthidentifier is a fourth value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel;

if the channel bonding identifier is the second value, and the bandwidthidentifier is a first value, the data transmission channel includesprimary 20 MHz and a secondary 40 MHz channel;

if the channel bonding identifier is the second value, and the bandwidthidentifier is a second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 80 MHz channel;

if the channel bonding identifier is the second value, and the bandwidthidentifier is a third value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 80MHz channel; or

if the channel bonding identifier is the second value, and the bandwidthidentifier is a fourth value, the data transmission channel includes aprimary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80MHz channel.

Manner 2:

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 40 MHz channel;

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel; or

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel, a secondary 40 MHz channel, and a secondary 80MHz channel.

Manner 3:

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 40 MHz channel;

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel; or

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 80 MHz channel.

Manner 4:

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 40 MHz channel;

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, a secondary 40 MHzchannel, and a secondary 80 MHz channel; or

if the bandwidth identifier is a fourth value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 80MHz channel.

Manner 5:

If the bandwidth identifier is a first value, the data transmissionchannel includes a primary 20 MHz channel;

if the bandwidth identifier is a second value, the data transmissionchannel includes a primary 20 MHz channel and a secondary 20 MHzchannel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the first value, the data transmission channel includes aprimary 20 MHz channel, a secondary 20 MHz channel, and a secondary 40MHz channel;

if the bandwidth identifier is a third value, and the channel bondingidentifier is the second value, the data transmission channel includes aprimary 20 MHz channel and a secondary 40 MHz channel; or

if the bandwidth identifier is a fourth value, the data transmissionchannel includes a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel.

It should be noted that a channel mapping relationship of manners 1 to 5is shown in FIG. 6 to FIG. 10, and detailed descriptions are alreadyprovided in Embodiment 1.

It should be noted that other channel indication manners in Embodiment 1to Embodiment 3 are also applied to the apparatus for indicating achannel in Embodiment 4.

This embodiment of the present invention provides an apparatus forindicating a channel in a wireless local area network WLAN. A basebandcircuit generates a physical protocol data unit PPDU, the PPDU includesa preamble field and a data field, a high efficiency signal fieldHE-SIG-A of the preamble field includes a bandwidth identifier and asecondary 20 MHz channel identifier, and when the bandwidth identifierindicates that a data transmission channel is greater than 40 MHz, thesecondary 20 MHz channel identifier is used to indicate whether asecondary 20 MHz channel is available. In the foregoing manner, adiscontinuous channel in a frequency domain in a wireless local areanetwork is indicated, an available data transmission channel isimproved, and a system throughput is increased.

Embodiment 5

Embodiment 5 of the present invention provides a method, which isapplied to a WLAN, for indicating a channel. The method may be appliedto a station, for example, the AP and the STA 1 to the STA 3 in FIG. 2.The station may support a next-generation WLAN standard, for example,the 802.11ax standard.

In this embodiment, a data transmission channel is indicated by using abandwidth identifier in a PPDU, and the bandwidth (BW) identifierincludes at least three bits.

The data transmission channel includes the following eight modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel, a secondary 20 MHz channel, and atleast one 20 MHz channel of a secondary 40 MHz channel.

Mode 4: At least a primary 20 MHz channel and a 20 MHz channel of asecondary 40 MHz channel are included, and the location of the 20 MHzchannel is opposite parity comparing with a location of the primary 20MHz channel, and, any 20 MHz channel of a secondary 80 MHz channel isnot included.

The opposite parity herein means that in descending order or inascending order of frequencies, one 20 MHz channel is on a 20 MHzchannel numbered by using an odd number, and the other 20 MHz channel ison a 20 MHz channel numbered by using an even number.

Mode 5: At least a primary 20 MHz channel, a secondary 20 MHz channel,and at least one 20 MHz channel of a secondary 80 MHz channel areincluded.

Mode 6: At least a primary 20 MHz channel, a 20 MHz channel of asecondary 40 MHz channel and at least one 20 MHz channel of a secondary80 MHz channel are included, and the location of the 20 MHz channel ofthe secondary 40 MHz channel is opposite parity comparing with alocation of the primary 20 MHz channel.

Mode 7: At least a primary 20 MHz channel and a first 20 MHz channel oftwo 20 MHz channels are included, and the locations of the two 20 MHzchannels of a secondary 80 MHz channel are opposite parity comparingwith a location of the primary 20 MHz channel.

Mode 8: At least a primary 20 MHz channel and a second 20 MHz channel oftwo 20 MHz channels are included, and the locations of the two 20 MHzchannels of a secondary 80 MHz channel are opposite parity comparingwith a location of the primary 20 MHz channel.

The first 20 MHz channel and the second 20 MHz channel may be defined byusing different methods, and this is not limited in this patent. Forexample, the first 20 MHz channel is a 20 MHz channel, which has a lowerfrequency, of the two 20 MHz channels, and locations of the two 20 MHzchannels of the secondary 80 MHz channel are opposite parity comparingwith the location of the primary 20 MHz channel, and the second 20 MHzchannel is a 20 MHz channel, which has a higher frequency, of the two 20MHz channels, and locations of the two 20 MHz channels of the secondary80 MHz channel are opposite parity comparing with the location of theprimary 20 MHz channel. Alternatively, a contrary case is alsoapplicable. For another example, the first 20 MHz channel is a 20 MHzchannel, whose rate of frequency separation to the primary 20 MHzchannel is smaller, of the two 20 MHz channels of the secondary 80 MHzchannel, and locations of the two 20 MHz channels are opposite paritycomparing with the location of the primary 20 MHz channel, and thesecond 20 MHz channel is a 20 MHz channel, whose rate of frequencyseparation to the primary 20 MHz channel is larger, of the two 20 MHzchannels of the secondary 80 MHz channel, and locations of the two 20MHz channels are opposite parity comparing with the location of theprimary 20 MHz channel. Alternatively, a contrary case is alsoapplicable.

It should be noted that when a channel is a primary 20 MHz channel and a20 MHz channel of secondary 40 MHz, whose location is the same parity asthat of the primary 20 MHz channel, mode 3 or mode 4 may be indicated.With such a result, when receiving a part of an HE-SIG-B on the primary20 MHz channel, a receiving station attempts to receive the other partof the HE-SIG-B on a secondary 20 MHz channel or a 20 MHz channel ofsecondary 40 MHz, whose location is opposite parity comparing with thatof the primary 20 MHz channel, but the receiving fails. No informationrelated to the HE-SIG-B is transmitted on a 20 MHz channel or the 20 MHzchannel of secondary 40 MHz, whose location is opposite parity comparingwith that of the primary 20 MHz channel. Therefore, the receivingfailure does not bring any information loss.

It should be added that when the channel includes the primary 20 MHzchannel and at least one 20 MHz channel of secondary 80 MHz, but doesnot include any 20 MHz channel whose location is opposite paritycomparing with that of the primary 20 MHz channel, mode 5, 6, 7, or 8may be indicated. With such a result, when receiving a part of anHE-SIG-B on the primary 20 MHz channel, a receiving station attempts toreceive the other part of the HE-SIG-B on the 20 MHz channel whoselocation is opposite parity comparing with that of the primary 20 MHzchannel and that is indicated in the mode, but the receiving fails. Noinformation related to the HE-SIG-B is transmitted on the 20 MHz channelwhose location is opposite parity comparing with that of the primary 20MHz channel. Therefore, the receiving failure does not bring anyinformation loss.

A correspondence between a bandwidth identifier and the eight modes isnot limited in the present invention, and the following correspondingmanner is preferably selected:

Bandwidth identifier 000 001 010 011 100 101 110 111 Mode Mode Mode ModeMode Mode 5 Mode 6 Mode 7 Mode 8 1 2 3 4

A correspondence between the eight modes and the channel is shown inTable 11.

TABLE 11 Bandwidth range of a Mode channel Actually used channel 1  20MHz 0 2  40 MHz (0, 1) 3  80 MHz (0, 1, 2) (0, 1, 3) (0, 1, 2, 3) 4  80MHz (0, 3) (0, 1, 3) (0, 2, 3) (0, 1, 2, 3) 5 160 MHz (0, 1, 4) (0, 1,2, 4) (0, 1, 5) (0, 1, 2, 5) (0, 1, 6) (0, 1, 2, 6) (0, 1, 7) (0, 1, 2,7) (0, 1, 4, 5) (0, 1, 2, 4, 5) (0, 1, 4, 6) (0, 1, 2, 4, 6) (0, 1, 4,7) (0, 1, 2, 4, 7) (0, 1, 5, 6) (0, 1, 2, 5, 6) (0, 1, 5, 7) (0, 1, 2,5, 7) (0, 1, 6, 7) (0, 1, 2, 6, 7) (0, 1, 4, 5, 6) (0, 1, 2, 4, 5, 6)(0, 1, 4, 5, 7) (0, 1, 2, 4, 5, 7) (0, 1, 4, 6, 7) (0, 1, 2, 4, 6, 7)(0, 1, 5, 6, 7) (0, 1, 2, 5, 6, 7) (0, 1, 4, 5, 6, 7) (0, 1, 2, 4, 5, 6,7) (0, 1, 3, 4) (0, 1, 2, 3, 4) (0, 1, 3, 5) (0, 1, 2, 3, 5) (0, 1, 3,6) (0, 1, 2, 3, 6) (0, 1, 3, 7) (0, 1, 2, 3, 7) (0, 1, 3, 4, 5) (0, 1,2, 3, 4, 5) (0, 1, 3, 4, 6) (0, 1, 2, 3, 4, 6) (0, 1, 3, 4, 7) (0, 1, 2,3, 4, 7) (0, 1, 3, 5, 6) (0, 1, 2, 3, 5, 6) (0, 1, 3, 5, 7) (0, 1, 2, 3,5, 7) (0, 1, 3, 6, 7) (0, 1, 2, 3, 6, 7) (0, 1, 3, 4, 5, 6) (0, 1, 2, 3,4, 5, 6) (0, 1, 3, 4, 5, 7) (0, 1, 2, 3, 4, 5, 7) (0, 1, 3, 4, 6, 7) (0,1, 2, 3, 4, 6, 7) (0, 1, 3, 5, 6, 7) (0, 1, 2, 3, 5, 6, 7) (0, 1, 3, 4,5, 6, 7) (0, 1, 2, 3, 4, 5, 6, 7) 6 160 MHz (0, 3, 4) (0, 1, 3, 4) (0,3, 5) (0, 1, 3, 5) (0, 3, 6) (0, 1, 3, 6) (0, 3, 7) (0, 1, 3, 7) (0, 3,4, 5) (0, 1, 3, 4, 5) (0, 3, 4, 6) (0, 1, 3, 4, 6) (0, 3, 4, 7) (0, 1,3, 4, 7) (0, 3, 5, 6) (0, 1, 3, 5, 6) (0, 3, 5, 7) (0, 1, 3, 5, 7) (0,3, 6, 7) (0, 1, 3, 6, 7) (0, 3, 4, 5, 6) (0, 1, 3, 4, 5, 6) (0, 3, 4, 5,7) (0, 1, 3, 4, 5, 7) (0, 3, 4, 6, 7) (0, 1, 3, 4, 6, 7) (0, 3, 5, 6, 7)(0, 1, 3, 5, 6, 7) (0, 3, 4, 5, 6, 7) (0, 1, 3, 4, 5, 6, 7) (0, 2, 3, 4)(0, 1, 2, 3, 4) (0, 2, 3, 5) (0, 1, 2, 3, 5) (0, 2, 3, 6) (0, 1, 2, 3,6) (0, 2, 3, 7) (0, 1, 2, 3, 7) (0, 2, 3, 4, 5) (0, 1, 2, 3, 4, 5) (0,2, 3, 4, 6) (0, 1, 2, 3, 4, 6) (0, 2, 3, 4, 7) (0, 1, 2, 3, 4, 7) (0, 2,3, 5, 6) (0, 1, 2, 3, 5, 6) (0, 2, 3, 5, 7) (0, 1, 2, 3, 5, 7) (0, 2, 3,6, 7) (0, 1, 2, 3, 6, 7) (0, 2, 3, 4, 5, 6) (0, 1, 2, 3, 4, 5, 6) (0, 2,3, 4, 5, 7) (0, 1, 2, 3, 4, 5, 7) (0, 2, 3, 4, 6, 7) (0, 1, 2, 3, 4, 6,7) (0, 2, 3, 5, 6, 7) (0, 1, 2, 3, 5, 6, 7) (0, 2, 3, 4, 5, 6, 7) (0, 1,2, 3, 4, 5, 6, 7) 7 160 MHz (0, 5) (0, 5, 7) (0, 5, 1) (0, 5, 7, 1) (0,5, 2) (0, 5, 7, 2) (0, 5, 3) (0, 5, 7, 3) (0, 5, 4) (0, 5, 7, 4) (0, 5,6) (0, 5, 7, 6) (0, 5, 1, 2) (0, 5, 7, 1, 2) (0, 5, 1, 3) (0, 5, 7, 1,3) (0, 5, 1, 4) (0, 5, 7, 1, 4) (0, 5, 1, 6) (0, 5, 7, 1, 6) (0, 5, 2,3) (0, 5, 7, 2, 3) (0, 5, 2, 4) (0, 5, 7, 2, 4) (0, 5, 2, 6) (0, 5, 7,2, 6) (0, 5, 3, 4) (0, 5, 7, 3, 4) (0, 5, 3, 6) (0, 5, 7, 3, 6) (0, 5,4, 6) (0, 5, 7, 4, 6) (0, 5, 3, 4, 6) (0, 5, 7, 3, 4, 6) (0, 5, 2, 4, 6)(0, 5, 7, 2, 4, 6) (0, 5, 2, 3, 6) (0, 5, 7, 2, 3, 6) (0, 5, 2, 3, 4)(0, 5, 7, 2, 3, 4) (0, 5, 1, 4, 6) (0, 5, 7, 1, 4, 6) (0, 5, 1, 3, 6)(0, 5, 7, 1, 3, 6) (0, 5, 1, 3, 4) (0, 5, 7, 1, 3, 4) (0, 5, 1, 2, 6)(0, 5, 7, 1, 2, 6) (0, 5, 1, 2, 4) (0, 5, 7, 1, 2, 4) (0, 5, 1, 2, 3)(0, 5, 7, 1, 2, 3) (0, 5, 1, 2, 3, 4) (0, 5, 7, 1, 2, 3, 4) (0, 5, 1, 2,3, 6) (0, 5, 7, 1, 2, 3, 6) (0, 5, 1, 2, 4, 6) (0, 5, 7, 1, 2, 4, 6) (0,5, 1, 3, 4, 6) (0, 5, 7, 1, 3, 4, 6) (0, 5, 2, 3, 4, 6) (0, 5, 7, 2, 3,4, 6) (0, 5, 1, 2, 3, 4, 6) (0, 5, 7, 1, 2, 3, 4, 6) 8 160 MHz (0, 7)(0, 5, 7) (0, 7, 1) (0, 5, 7, 1) (0, 7, 2) (0, 5, 7, 2) (0, 7, 3) (0, 5,7, 3) (0, 7, 4) (0, 5, 7, 4) (0, 7, 6) (0, 5, 7, 6) (0, 7, 1, 2) (0, 5,7, 1, 2) (0, 7, 1, 3) (0, 5, 7, 1, 3) (0, 7, 1, 4) (0, 5, 7, 1, 4) (0,7, 1, 6) (0, 5, 7, 1, 6) (0, 7, 2, 3) (0, 5, 7, 2, 3) (0, 7, 2, 4) (0,5, 7, 2, 4) (0, 7, 2, 6) (0, 5, 7, 2, 6) (0, 7, 3, 4) (0, 5, 7, 3, 4)(0, 7, 3, 6) (0, 5, 7, 3, 6) (0, 7, 4, 6) (0, 5, 7, 4, 6) (0, 7, 3, 4,6) (0, 5, 7, 3, 4, 6) (0, 7, 2, 4, 6) (0, 5, 7, 2, 4, 6) (0, 7, 2, 3, 6)(0, 5, 7, 2, 3, 6) (0, 7, 2, 3, 4) (0, 5, 7, 2, 3, 4) (0, 7, 1, 4, 6)(0, 5, 7, 1, 4, 6) (0, 7, 1, 3, 6) (0, 5, 7, 1, 3, 6) (0, 7, 1, 3, 4)(0, 5, 7, 1, 3, 4) (0, 7, 1, 2, 6) (0, 5, 7, 1, 2, 6) (0, 7, 1, 2, 4)(0, 5, 7, 1, 2, 4) (0, 7, 1, 2, 3) (0, 5, 7, 1, 2, 3) (0, 7, 1, 2, 3, 4)(0, 5, 7, 1, 2, 3, 4) (0, 7, 1, 2, 3, 6) (0, 5, 7, 1, 2, 3, 6) (0, 7, 1,2, 4, 6) (0, 5, 7, 1, 2, 4, 6) (0, 7, 1, 3, 4, 6) (0, 5, 7, 1, 3, 4, 6)(0, 7, 2, 3, 4, 6) (0, 5, 7, 2, 3, 4, 6) (0, 7, 1, 2, 3, 4, 6) (0, 5, 7,1, 2, 3, 4, 6) Notes: (0, 2) belongs to mode 3 or mode 4. Notes: (0, 4),(0, 6), (0, 4, 6), (0, 2, 4), (0, 2, 6), and (0, 2, 4, 6) belong to mode5, or mode 6, or mode 7, or mode 8.

The channel identifier used in the table is a logical identifier of thechannel. Generally, a channel identifier 0 indicates a primary 20 MHzchannel, a channel identifier 1 indicates a secondary 20 MHz channel,channel identifiers 2 and 3 indicate a secondary 40 MHz channel, andchannel identifiers 4 to 7 indicate a secondary 80 MHz channel. Afrequently used mapping relationship between a channel identifier and achannel is described above. Another mapping relationship between achannel identifier and a channel also exists. This is not limited in thepresent invention.

For convenience of description below, an HE-SIG-B on a primary channelis referred to as an HE-SIG-B 1 herein. As shown in FIG. 6, FIG. 7, FIG.8, and FIG. 9, the HE-SIG-B 1 is copied on a channel whose location isthe same parity as that of the primary channel, and a common part of theHE-SIG-B 1 includes RU allocation signaling of a primary 20 MHz channeland a 20 MHz channel whose location is the same parity as that of theprimary channel. A common part of an HE-SIG-B 2 includes RU allocationsignaling of a 20 MHz channel whose location is opposite paritycomparing with that of the primary 20 MHz channel, and is copied on themultiple 20 MHz channels. It is assumed that RU allocation signaling ofeach 20 MHz channel has a length of N bits, and eight bits is used as anexample in the following descriptions.

Each of the foregoing eight modes carries two pieces of information. Thefirst piece of information indicates a length of the common part of theHE-SIG-B 1 and a length of the common part of the HE-SIG-B 2 to areceiving node (herein, the length of the common part of the HE-SIG-B 1is equal to the length of the common part of the HE-SIG-B 2). The secondpiece of information indicates on which 20 MHz channel the receivingnode receives the HE-SIG-B 2. It should be noted herein that thereceiving node is bound to receive the HE-SIG-B 1 on the primary 20 MHzchannel. For example, mode 3 indicates to the receiving node that boththe length of the common part of the HE-SIG-B 1 and the length of thecommon part of the HE-SIG-B 2 are 16 bits (statistics on a length of RUallocation signaling of only a 20 MHz channel is collected herein), andthe HE-SIG-B 2 is received on a channel whose logical identifier is 1.For another example, mode 8 indicates to the receiving node that boththe length of the common part of the HE-SIG-B 1 and the length of thecommon part of the HE-SIG-B 2 are 32 bits, and the HE-SIG-B 2 isreceived on a 20 M channel whose logical identifier is 7. Therefore, theforegoing eight modes indicate that the receiving node can correctlyreceive the HE-SIG-B 1 and the HE-SIG-B 2.

In addition, special RU allocation signaling, that is, 242(0), exists inthe RU allocation signaling of an HE-SIG-B 20 MHz channel, and indicatesthat 242 subcarriers that can transmit information and that correspondto the 20 MHz channel do not transmit data of any station. That is, the20 MHz channel does not perform data transmission.

With reference to the eight modes of the HE-SIG-A and the RU allocationsignaling, which is included in the common parts of the HE-SIG-B 1 andthe HE-SIG-B 2, of each 20 MHz, the receiving node can learn that datais received on which channels. For example, it is assumed that a datatransmission channel is (0 1 2), and a sending node sets a bandwidthidentifier bit of an HE-SIG-A in a physical layer preamble to mode 3. Inaddition, the HE-SIG-B 1 includes RU allocation signaling of a channel 0and a channel 2, and the HE-SIG-B 2 includes RU allocation signaling ofa channel 1 and a channel 3. The RU allocation signaling of the channel3 is 242(0). After receiving the HE-SIG-A, a receiver learns, accordingto the bandwidth identifier bit, that mode 3 is used. That is, both thelength of the common part of the HE-SIG-B 1 and the length of the commonpart of the HE-SIG-B 2 are 16 bits. The HE-SIG-B 1 is received on achannel whose logical identifier is 0 (the primary 20 MHz channel), andthe HE-SIG-B 2 is received on a channel whose logical identifier is 1.With reference to the RU allocation signaling 242(0), which is includedin the HE-SIG-B 2, of the channel whose logical identifier is 3, it islearned that the data transmission channel is (0 1 2).

It should be noted that actually used channels indicated in each mode inTable 11 are overlapped. However, this does not affect that thereceiving node learns a length of a common part of an HE-SIG-B andlearns that the HE-SIG-B 2 is received on which 20 MHz channel.Therefore, the foregoing mode indication may correctly tell thereceiving node that data transmission is performed on which 20 MHzchannels. In a implementation, the actually used channels that areoverlapped are used in only one mode, so that actually used channelsindicated in all the modes are not overlapped. For example, cases inwhich actually used channels that are overlapped and that are indicatedin mode 3 and mode 4 in Table 11 are (0, 1, 3), (0, 1, 2, 3), and (0,2). To avoid overlapping, the foregoing three cases of actually usedchannels are used only in mode 3, and are removed from mode 4. It shouldbe noted that the foregoing channel overlapping cases are alsoapplicable to another embodiment.

It should be noted that different orders of channel identifiers in Table11 do not affect actually used channels. For example, actually usedchannels indicated by channel identifiers (0, 7, 1, 2) and channelidentifiers (0, 1, 2, 7) are the same.

This embodiment of the present invention provides a method forindicating a channel in a wireless local area network WLAN. A sendingstation generates and sends a physical protocol data unit PPDU, the PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier,and the bandwidth identifier is used to indicate a data transmissionchannel. In the foregoing manner, a discontinuous channel in a frequencydomain in a wireless local area network is indicated, an available datatransmission channel is improved, and a system throughput is increased.

Embodiment 6

Embodiment 6 of the present invention provides a method, which isapplied to a WLAN, for indicating a channel. The method may be appliedto a station, for example, the AP and the STA 1 to the STA 3 in FIG. 2.The station may support a next-generation WLAN standard, for example,the 802.11ax standard.

In this embodiment, a data transmission channel is indicated by using abandwidth identifier in a PPDU, and the bandwidth (BW) identifierincludes at least three bits.

The data transmission channel includes the following eight modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel, a secondary 20 MHz channel, and atleast one 20 MHz channel of a secondary 40 MHz channel.

Mode 4: At least a primary 20 MHz channel and a 20 MHz channel of asecondary 40 MHz channel are included, and location of the 20 MHzchannel is opposite parity comparing with a location of the primary 20MHz channel, and, any 20 MHz channel of a secondary 80 MHz channel isnot included.

Mode 5: a primary 20 MHz channel and a 20 MHz channel of a secondary 40MHz channel are included, and location of the 20 MHz channel is the sameparity as that of the primary 20 MHz channel.

Mode 6: At least a primary 20 MHz channel, a secondary 20 MHz channel,and at least one 20 MHz channel of a secondary 80 MHz channel areincluded.

Mode 7: At least a primary 20 MHz channel, a 20 MHz channel of asecondary 40 MHz channel, and at least one 20 MHz channel of a secondary80 MHz channel are included, and a location of the 20 MHz channel of asecondary 40 MHz channel is opposite parity comparing with a location ofthe primary 20 MHz channel.

Mode 8: a primary 20 MHz channel, a 20 MHz channel of a secondary 40 MHzchannel and at least one 20 MHz channel of a secondary 80 MHz channelare included, and a location of the 20 MHz channel of a secondary 40 MHzchannel is the same parity as a location of the primary 20 MHz channel.

A correspondence between the bandwidth identifier and the eight modes isnot limited in the present invention, and the following correspondingmanner is introduced for use:

Bandwidth identifier 000 001 010 011 100 101 110 111 Mode Mode Mode ModeMode Mode 5 Mode 6 Mode 7 Mode 8 1 2 3 4

A correspondence between the eight modes and the channel is shown inTable 12.

TABLE 12 Bandwidth range of a Mode channel Actually used channel 1 20MHz (0) 2 40 MHz (0, 1) 3 80 MHz (0, 1, 2) (0, 1, 3) (0, 1, 2, 3) 4 80MHz (0, 3) (0, 1, 3) (0, 2, 3) (0, 1, 2, 3) 5 80 MHz (0, 2) 6 160 MHz (0, 1, 4) (0, 1, 2, 4) (0, 1, 5) (0, 1, 2, 5) (0, 1, 6) (0, 1, 2, 6) (0,1, 7) (0, 1, 2, 7) (0, 1, 4, 5) (0, 1, 2, 4, 5) (0, 1, 4, 6) (0, 1, 2,4, 6) (0, 1, 4, 7) (0, 1, 2, 4, 7) (0, 1, 5, 6) (0, 1, 2, 5, 6) (0, 1,5, 7) (0, 1, 2, 5, 7) (0, 1, 6, 7) (0, 1, 2, 6, 7) (0, 1, 4, 5, 6) (0,1, 2, 4, 5, 6) (0, 1, 4, 5, 7) (0, 1, 2, 4, 5, 7) (0, 1, 4, 6, 7) (0, 1,2, 4, 6, 7) (0, 1, 5, 6, 7) (0, 1, 2, 5, 6, 7) (0, 1, 4, 5, 6, 7) (0, 1,2, 4, 5, 6, 7) (0, 1, 3, 4) (0, 1, 2, 3, 4) (0, 1, 3, 5) (0, 1, 2, 3, 5)(0, 1, 3, 6) (0, 1, 2, 3, 6) (0, 1, 3, 7) (0, 1, 2, 3, 7) (0, 1, 3, 4,5) (0, 1, 2, 3, 4, 5) (0, 1, 3, 4, 6) (0, 1, 2, 3, 4, 6) (0, 1, 3, 4, 7)(0, 1, 2, 3, 4, 7) (0, 1, 3, 5, 6) (0, 1, 2, 3, 5, 6) (0, 1, 3, 5, 7)(0, 1, 2, 3, 5, 7) (0, 1, 3, 6, 7) (0, 1, 2, 3, 6, 7) (0, 1, 3, 4, 5, 6)(0, 1, 2, 3, 4, 5, 6) (0, 1, 3, 4, 5, 7) (0, 1, 2, 3, 4, 5, 7) (0, 1, 3,4, 6, 7) (0, 1, 2, 3, 4, 6, 7) (0, 1, 3, 5, 6, 7) (0, 1, 2, 3, 5, 6, 7)(0, 1, 3, 4, 5, 6, 7) (0, 1, 2, 3, 4, 5, 6, 7) 7 160 MHz  (0, 3, 4) (0,1, 3, 4) (0, 3, 5) (0, 1, 3, 5) (0, 3, 6) (0, 1, 3, 6) (0, 3, 7) (0, 1,3, 7) (0, 3, 4, 5) (0, 1, 3, 4, 5) (0, 3, 4, 6) (0, 1, 3, 4, 6) (0, 3,4, 7) (0, 1, 3, 4, 7) (0, 3, 5, 6) (0, 1, 3, 5, 6) (0, 3, 5, 7) (0, 1,3, 5, 7) (0, 3, 6, 7) (0, 1, 3, 6, 7) (0, 3, 4, 5, 6) (0, 1, 3, 4, 5, 6)(0, 3, 4, 5, 7) (0, 1, 3, 4, 5, 7) (0, 3, 4, 6, 7) (0, 1, 3, 4, 6, 7)(0, 3, 5, 6, 7) (0, 1, 3, 5, 6, 7) (0, 3, 4, 5, 6, 7) (0, 1, 3, 4, 5, 6,7) (0, 2, 3, 4) (0, 1, 2, 3, 4) (0, 2, 3, 5) (0, 1, 2, 3, 5) (0, 2, 3,6) (0, 1, 2, 3, 6) (0, 2, 3, 7) (0, 1, 2, 3, 7) (0, 2, 3, 4, 5) (0, 1,2, 3, 4, 5) (0, 2, 3, 4, 6) (0, 1, 2, 3, 4, 6) (0, 2, 3, 4, 7) (0, 1, 2,3, 4, 7) (0, 2, 3, 5, 6) (0, 1, 2, 3, 5, 6) (0, 2, 3, 5, 7) (0, 1, 2, 3,5, 7) (0, 2, 3, 6, 7) (0, 1, 2, 3, 6, 7) (0, 2, 3, 4, 5, 6) (0, 1, 2, 3,4, 5, 6) (0, 2, 3, 4, 5, 7) (0, 1, 2, 3, 4, 5, 7) (0, 2, 3, 4, 6, 7) (0,1, 2, 3, 4, 6, 7) (0, 2, 3, 5, 6, 7) (0, 1, 2, 3, 5, 6, 7) (0, 2, 3, 4,5, 6, 7) (0, 1, 2, 3, 4, 5, 6, 7) 8 160 MHz  (0, 2, 4) (0, 2, 5) (0, 2,6) (0, 2, 7) (0, 2, 4, 5) (0, 2, 4, 6) (0, 2, 4, 7) (0, 2, 5, 6) (0, 2,5, 7) (0, 2, 6, 7) (0, 2, 4, 5, 6) (0, 2, 4, 5, 7) (0, 2, 4, 6, 7) (0,2, 5, 6, 7) (0, 2, 4, 5, 6, 7)

The channel identifier used in the table is a logical identifier of thechannel. Generally, a channel identifier 0 indicates a primary 20 MHzchannel, a channel identifier 1 indicates a secondary 20 MHz channel,channel identifiers 2 and 3 indicate a secondary 40 MHz channel, andchannel identifiers 4 to 7 indicate a secondary 80 MHz channel. Afrequently used mapping relationship between a channel identifier and achannel is described above. Another mapping relationship between achannel identifier and a channel also exists. This is not limited in thepresent invention.

It should be noted that different orders of channel identifiers in Table12 do not affect actually used channels. For example, actually usedchannels indicated by channel identifiers (0, 7, 1, 2) and channelidentifiers (0, 1, 2, 7) are the same.

Only one HE-SIG-B exists in mode 5 and mode 8. In this case, theHE-SIG-B includes RU allocation signaling of all 20 M channels. Only onepiece of information, that is, a length of the HE-SIG-B, is carried inmode 5 and mode 8. In the other modes other than mode 5 and mode 8, RUallocation signaling included in common parts of the HE-SIG-B 1 and theHE-SIG-B 2 are the same as those in the transmission manner inEmbodiment 5. Descriptions of overlapping cases indicated in the modesin the table are the same as those in Embodiment 5, and details are notdescribed herein again.

This embodiment of the present invention provides a method forindicating a channel in a wireless local area network WLAN. A sendingstation generates and sends a physical protocol data unit PPDU, the PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier,and the bandwidth identifier is used to indicate a data transmissionchannel. In the foregoing manner, a discontinuous channel in a frequencydomain in a wireless local area network is indicated, an available datatransmission channel is improved, and a system throughput is increased.

Embodiment 7

Embodiment 7 of the present invention provides a method, which isapplied to a WLAN, for indicating a channel. The method may be appliedto a station, for example, the AP and the STA 1 to the STA 3 in FIG. 2.The station may support a next-generation WLAN standard, for example,the 802.11ax standard.

In this embodiment, a data transmission channel is indicated by using abandwidth identifier in a high efficiency signal field HE-SIG-A of apreamble field in a PPDU, and the bandwidth (BW) identifier includes atleast three bits.

The data transmission channel includes the following eight modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel.

Mode 5: a primary 20 MHz channel and a 20 MHz channel of a secondary 40MHz channel, and the location of the 20 MHz channel is opposite paritycomparing with that of the primary 20 MHz channel.

Mode 6: a primary 20 MHz channel and a secondary 40 MHz channel.

Mode 7: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 80 MHz channel.

Mode 8: a primary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel.

A correspondence between the bandwidth identifier and the eight modes isnot limited in the present invention, and the following correspondingmanner is introduced for use:

Bandwidth identifier 000 001 010 011 100 101 110 111 Mode Mode Mode ModeMode Mode 5 Mode 6 Mode 7 Mode 8 1 2 3 4

For example, a correspondence between the eight modes and the channel isshown in FIG. 25.

This embodiment of the present invention provides a method forindicating a channel in a wireless local area network WLAN. A sendingstation generates and sends a physical protocol data unit PPDU, the PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier,and the bandwidth identifier is used to indicate a data transmissionchannel. In the foregoing manner, a discontinuous channel in a frequencydomain in a wireless local area network is indicated, an available datatransmission channel is improved, and a system throughput is increased.

Embodiment 8

Embodiment 8 of the present invention provides a method, which isapplied to a WLAN, for indicating a channel. The method may be appliedto a station, for example, the AP and the STA 1 to the STA 3 in FIG. 2.The station may support a next-generation WLAN standard, for example,the 802.11ax standard.

In this embodiment, a data transmission channel is indicated by using abandwidth identifier in a high efficiency signal field HE-SIG-A of apreamble field in a PPDU, and the bandwidth (BW) identifier includes atleast three bits.

The data transmission channel includes the following eight modes:

Mode 1: a primary 20 MHz channel.

Mode 2: a primary 20 MHz channel and a secondary 20 MHz channel.

Mode 3: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 40 MHz channel.

Mode 4: a primary 20 MHz channel, a secondary 20 MHz channel, asecondary 40 MHz channel, and a secondary 80 MHz channel.

Mode 5: a primary 20 MHz channel and a secondary 40 MHz channel.

Mode 6: a primary 20 MHz channel, a secondary 20 MHz channel, and one 20MHz channel of a secondary 40 MHz channel.

It should be noted that mode 6 includes two implementations. The firstimplementation in mode 6 is a primary 20 MHz channel, a secondary 20 MHzchannel, and a channel, whose location is the same parity as that of theprimary 20 MHz channel, of a secondary 40 MHz channel. The secondimplementation in mode 6 is a primary 20 MHz channel, a secondary 20 MHzchannel, and a channel, whose location is opposite parity comparing withthat of the primary 20 MHz channel, of a secondary 40 MHz channel.

Mode 7: a primary 20 MHz channel, a secondary 20 MHz channel, and asecondary 80 MHz channel.

Mode 8: a primary 20 MHz channel, a secondary 40 MHz channel, and asecondary 80 MHz channel.

A correspondence between the bandwidth identifier and the eight modes isnot limited in the present invention, and the following correspondingmanner is introduced for use:

Bandwidth identifier 000 001 010 011 100 101 110 111 Mode Mode Mode ModeMode Mode 5 Mode 6 Mode 7 Mode 8 1 2 3 4

For example, a correspondence between the eight modes and the channel isshown in FIG. 26 or FIG. 27.

This embodiment of the present invention provides a method forindicating a channel in a wireless local area network WLAN. A sendingstation generates and sends a physical protocol data unit PPDU, the PPDUincludes a preamble field and a data field, a high efficiency signalfield HE-SIG-A of the preamble field includes a bandwidth identifier,and the bandwidth identifier is used to indicate a data transmissionchannel. In the foregoing manner, a discontinuous channel in a frequencydomain in a wireless local area network is indicated, an available datatransmission channel is improved, and a system throughput is increased.

The foregoing embodiments are merely intended for describing thetechnical solutions of the present invention, but not for limiting thepresent invention. Although the present invention is described in detailwith reference to the foregoing embodiments, persons of ordinary skillin the art should understand that they may still make modifications tothe technical solutions described in the foregoing embodiments or makeequivalent replacements to some technical features thereof, withoutdeparting from the scope of the technical solutions of the embodimentsof the present invention.

What is claimed is:
 1. A method for indicating a channel in a wirelesslocal area network (WLAN), comprising: generating a physical protocoldata unit (PPDU), wherein the PPDU includes a preamble field and a datafield, a high efficiency signal field (HE-SIG-A) of the preamble fieldincludes a bandwidth identifier; and, the bandwidth identifier is usedto indicate a data transmission channel, the bandwidth identifierincludes at least three bits; sending the PPDU.
 2. The method accordingto claim 1, wherein the bandwidth identifier is a first value, the firstvalue indicates a first mode of the data transmission channel; in thefirst mode, at least a primary 20 MHz channel and a 20 MHz channel of asecondary 40 MHz channel are included, and a location of the 20 MHzchannel of the secondary 40 MHz channel is opposite parity comparingwith a location of the primary 20 MHz channel, and, any 20 MHz channelof a secondary 80 MHz channel is not included.
 3. The method accordingto claim 2, wherein in the first mode, the primary 20 MHz channel, andthe secondary 40 MHz channel are included, and, any 20 MHz channel ofthe secondary 80 MHz channel is not included.
 4. The method according toclaim 3, wherein the at least three bits of the first value is
 100. 5.The method according to claim 1, wherein the bandwidth identifier is asecond value, the second value indicates a second mode of the datatransmission channel; in the second mode, a primary 20 MHz channel, asecondary 20 MHz channel, and at least one 20 MHz channel of a secondary40 MHz channel are included.
 6. The method according to claim 5, whereinin the second mode, the primary 20 MHz channel, the secondary 20 MHzchannel, and one 20 MHz channel of the secondary 40 MHz channel areincluded.
 7. The method according to claim 6, wherein the at least threebits of the second value is
 101. 8. The method according to claim 1,wherein the bandwidth identifier is a third value, the third valueindicates a third mode of the data transmission channel; in the thirdmode, at least a primary 20 MHz channel, and a 20 MHz channel of asecondary 40 MHz channel, and at least one 20 MHz channel of a secondary80 MHz channel are included, and a location of the 20 MHz channel of thesecondary 40 MHz channel is opposite parity comparing with a location ofthe primary 20 MHz channel.
 9. The method according to claim 8, whereinin the third mode, the primary 20 MHz channel, and the secondary 40 MHzchannel, and at least one 20 MHz channel of the secondary 80 MHz channelare included.
 10. The method according to claim 1, wherein the bandwidthidentifier is a fourth value, the fourth value indicates a fourth modeof the data transmission channel; in the fourth mode, at least a primary20 MHz channel, a secondary 20 MHz channel, and at least one 20 MHzchannel of a secondary 80 MHz channel are included.
 11. The methodaccording to claim 1, wherein the data transmission channel isdiscontinuous in frequency domain.
 12. An apparatus for indicating achannel in a wireless local area network (WLAN), comprising: a basebandcircuit, configured to generate a physical protocol data unit (PPDU),wherein the PPDU includes a preamble field and a data field, a highefficiency signal field (HE-SIG-A) of the preamble field includes abandwidth identifier; and the bandwidth identifier is used to indicate adata transmission, the bandwidth identifier includes at least threebits; a radio frequency circuit, configured to send the PPDU.
 13. Theapparatus according to claim 12, wherein the bandwidth identifier is afirst value, the first value indicates a first mode of the datatransmission channel; in the first mode, at least a primary 20 MHzchannel and a 20 MHz channel of a secondary 40 MHz channel are included,and a location of the 20 MHz channel of the secondary 40 MHz channel isopposite parity comparing with a location of the primary 20 MHz channel,and, any 20 MHz channel of a secondary 80 MHz channel is not included.14. The apparatus according to claim 13, wherein in the first mode, theprimary 20 MHz channel, and the secondary 40 MHz channel are included,and, any 20 MHz channel of the secondary 80 MHz channel is not included.15. The apparatus according to claim 14, wherein the at least three bitsof the first value is
 100. 16. The apparatus according to claim 12,wherein the bandwidth identifier is a second value, the second valueindicates a second mode of the data transmission channel; in the secondmode, a primary 20 MHz channel, a secondary 20 MHz channel, and at leastone 20 MHz channel of a secondary 40 MHz channel are included.
 17. Theapparatus according to claim 16, wherein in the second mode, the primary20 MHz channel, the secondary 20 MHz channel, and one 20 MHz channel ofthe secondary 40 MHz channel are included.
 18. The apparatus accordingto claim 17, wherein the at least three bits of the second value is 101.19. The apparatus according to claim 12, wherein the bandwidthidentifier is a third value, the third value indicates a third mode ofthe data transmission channel; in the third mode, at least a primary 20MHz channel, a 20 MHz channel of a secondary 40 MHz channel, and atleast one 20 MHz channel of a secondary 80 MHz channel are included, anda location of the 20 MHz channel of the secondary 40 MHz channel isopposite parity comparing with a location of the primary 20 MHz channel.20. The apparatus according to claim 19, wherein in the third mode, theprimary 20 MHz channel, and the secondary 40 MHz channel, and at leastone 20 MHz channel of the secondary 80 MHz channel are included.
 21. Theapparatus according to claim 12, wherein the bandwidth identifier is afourth value, the fourth value indicates a fourth mode of the datatransmission channel; in the fourth mode, at least a primary 20 MHzchannel, a secondary 20 MHz channel, and at least one 20 MHz channel ofa secondary 80 MHz channel are included.
 22. The apparatus according toclaim 12, wherein the data transmission channel is discontinuous infrequency domain.